A U.S. Department of Energy laboratory operated by Iowa State University

SCIENCE & TECHNOLOGY AT THE AMES LABORATORY

· Digital Detective Work

· Beauty Near Absolute Zero 

· Marvelous Metamaterials

Nanoscale Drug Delivery
Q

18

12

6

Ames Laboratory is a U.S. Department of 

Energy laboratory seeking solutions to en-

ergy-related problems through the explora-

tion of chemical, engineering, materials 

and mathematical sciences, and physics. 

Established in the 1940s with the suc-

cessful development of the most efficient 

process to produce high-purity uranium 

metal for atomic energy, Ames Lab now 

pursues much broader priorities than the 

materials research that has given the Lab 

international credibility. Responding to is-

sues of national concern, Ames Laboratory 

scientists are actively involved in innovative 

research, science education programs, the 

development of applied technologies and 

the quick transfer of such technologies 

to industry. Uniquely integrated within a 

university environment, the Lab stimulates 

creative thought and encourages scientific 

discovery, providing solutions to complex 

problems and educating tomorrow’s 

scientific talent.

Steve Karsjen, Editor

Kerry Gibson, Managing Editor

Saren Johnston, Contributing Editor

Grant Luhmann, Art Director

Rocky Dunkin, Graphics Intern

Copyright 2006 by Ames Laboratory. All 

rights reserved. For additional information 

about Ames Laboratory or topics covered 

in this publication, please contact: 

Editor, Inquiry

Ames Laboratory

111 TASF

Ames, Iowa 50011-3020

515-294-9557

www.ameslab.gov

Inquiry is published annually by the Ames 

Laboratory Office of Public Affairs. Iowa 

State University operates the Laboratory 

for the U.S. Department of Energy under 

contract W-7405-Eng-82. Located on 

the ISU campus, the Ames Laboratory 

is a member of the university’s Institute 

for Physical Research and Technology, a 

network of scientific research centers.
INQUIRY 2006 1

Contents

D E PA R T M E N T S

2 Director’s Letter

15 Milestones

23 Awards

24 Education

14

F E AT U R E S

4 Hiding in Plain Sight Using statistical measures, Midwest Forensics 

 Resource Center researchers are locating secretly 

 hidden computer files.

6 The Computational Chemistry “Toolbox” Stymied by problems of a molecular nature? Get help 

 from the quantum chemistry codes in GAMESS advises 

 theoretical chemist Mark Gordon.

10 Lead-free Europe Iver Anderson’s patented solder helps electronics

 manufacturers meet new European Union restrictions 

 on lead.

12 Nanoscale Drug Delivery

Using mesoporous silica nanoparticles, Victor Lin finds a 

 way to target sick cells while leaving healthy cells untreated.

16 Radical Means Don’t bother looking for iron(IV) in Fenton chemistry. 

 Go with OH radicals says chemist Andreja Bakac.

18 Cunning Patterns of Excelling Nature

Physicist Ruslan Prozorov knows that spectacular 

 physics and stunning beauty coexist quite naturally 

 near absolute zero.

20 Fast Backward Motion 

Physicist Costas Soukoulis is moving negative index 

 materials closer to the light – visible light, that is.

16

Cover photo: A micrograph of chemist Victor Lin’s mesoporous silica 

nanoparticles shows the tiny channels that can be filled with drugs that 

are released once the particle are absorbed by living cells.

Back cover: A glass condenser coil catches and reflects laboratory lights.

10
2 INQUIRY 2006

ELCOME TO THE 2006 ISSUE OF

Inquiry magazine. As I write this in early 

August, the clock is ticking down on the 

competitive bidding process for operation 

of Ames Laboratory. It’s the first time in 

the nearly 60-year history of the Lab that the Department 

of Energy will consider potential contractors besides Iowa 

State University, the Lab’s exclusive contractor since its 

inception. By the time you read this, the bidding process 

will be completed and the contract awarded. 

While the outcome of that process is unknown at 

this point, one thing is crystal clear — the quality of the 

research at Ames Laboratory continues to be world-class. For the second straight year and the 16th time overall, Ames 

Laboratory researchers have received an R&D100 Award. Mark Bryden, Gerrick Bivins, and Doug McCorkle have created 

software that takes large 3-D data sets and quickly converts them into images with which engineers can analyze and 

work. The software has been used to study ways to reduce emissions from power plants, decrease pollution from swine 

confinements and improve vehicle efficiency — the possibilities are almost limitless. You can read more about this exciting 

work in the Bryden group on the opposite page.

Senior physicist Costas Soukoulis won international recognition in December, coordinating a multinational team that 

received the Descartes Prize for Excellence in Scientific Collaborative Research, the European Union’s highest honor in the 

field of science. He and his collaborators received the prestigious award for creating a novel class of artificial metamaterials 

called left-handed materials, which exhibit negative refraction, bending light in the opposite direction to that seen in natural 

materials. You’ll find information on Dr. Soukoulis’ award and pioneering work on Pages 9 and 20.

Chemist Victor Lin continues to find exciting uses for tiny particles of silica – mesoporous nanoparticles. His latest effort 

utilizes them to deliver drugs within living cells and selectively release their pharmaceutical payload so that only targeted 

cells benefit from the drug while healthy cells are left unaffected. You can see the system in action beginning on Page 14.

One of the long-standing mysteries in organic chemistry – a field close to my heart – is the nature of the mechanism 

that triggers the Fenton reaction, one of the most powerful oxidizing reactions available for breaking apart organic compounds. Ames Lab senior scientist Andreja Bakac and her collaborators at two other universities, were able for the first 

time to produce and study a novel compound containing iron and effectively rule out its frequently speculated involvement 

in the Fenton reaction. Dr. Bakac’s work is detailed on Page 12.

Ames Laboratory’s education efforts continue to benefit the young people of Iowa and students from around the 

country. Teams from our Regional Middle School and High School Science Bowl competitions both finished in the prize 

money at their respective national contests, competing against often much larger schools from around the country. Our 

Science Undergraduate Laboratory Internship, or SULI, program brought another 10 undergraduate students from all over 

the United States to work closely with Ames Lab and Iowa State University research mentors in a variety of disciplines. 

And we’ve initiated a Laboratory Science Teacher Professional Development, or LSTPD, program that will bring 10 

middle school teachers from Iowa, Minnesota and South Dakota to the Lab to participate in the Teachers as Investigators 

program starting next summer. Through the program, teachers will conduct hands-on, discovery-based experiments with 

advanced equipment right here at the Lab and then learn how to bring exciting breakthroughs and frontiers of science into 

their classrooms.

As the research projects detailed in the pages of Inquiry demonstrate, Ames Laboratory is committed to finding 

solutions through innovative science. I hope that you enjoy learning about some of our recent successes, as well as our 

efforts to ensure that our country has outstanding scientists for the future.

 

 

W

From the Director
INQUIRY 2006 3

TEAM OF AMES LABORATORY AND IOWA STATE

University researchers has won a 2006 R&D 

100 Award for their development of a novel 

software engineering tool that greatly eases 

the problem-solving and decision-making 

processes for engineers. Their software tool, Texture 

Based Engineering Tools, or TBET, provides engineers an 

unrivaled means of interacting with large 3-D data sets to 

tackle complex engineering projects. The award-winning 

work has been supported by close to $1.3 million from the 

Ames Laboratory.

TBET is the brainchild of Ames Laboratory scientist 

Kenneth “Mark” Bryden, who is also the Iowa State University associate chair of mechanical engineering and an 

associate professor in that department. Co-developers are 

Gerrick Bivins, an ISU assistant scientist working in Bryden’s 

lab, and Douglas McCorkle, an ISU mechanical engineering doctoral student. Their win of a 2006 R&D100 Award 

brings the Laboratory’s total to16 since1984.

The winning of an R&D100 Award provides a mark of 

excellence known to industry, government and academia 

as proof that the product is one of the most innovative 

ideas of the year.

Applauding the Ames Lab and ISU accomplishment, 

Secretary of Energy Samuel W. Bodman said, “I congratulate the researchers who have won this award, which 

highlights the power and promise of DOE’s investments in 

science and technology. Through the efforts of dedicated 

and innovative scientists and engineers at our national 

laboratories, DOE is helping to enhance our nation’s energy, economic and national security.”

Echoing the Secretary’s praise, Ames Laboratory Director 

Tom Barton says, “The innovative, pioneering work coming 

from Mark Bryden and his research group is changing the 

way engineers can manage huge amounts of interactive 

data to maximize design and operational efficiency. The 

Ames Laboratory is proud to play this role in aiding American industry to maintain world-class competitiveness.”

Bryden says that Texture Based Engineering Tools is one 

component of an open-source engineering software package called VE-Suite that enables virtual engineering to take 

place. “There is nothing on the market that can do the job 

as quickly and intuitively,” Bryden emphasizes. 

The John Zink Company LLC, a recognized leader of 

advanced pollution-controlled systems, fire equipment and 

next-generation technologies, is taking advantage of TBET’s 

unique visualization capabilities in their efforts to improve 

designs of combustion systems.

 “The Texture Based Engineering Tools that are implemented in VE-Suite are critical to helping our engineers 

gain unparalleled insights into the computational fluid 

dynamics models of combustion systems,” says Christopher Jian, director of simulation technology solutions for 

John Zink. 

Bryden, Bivins and McCorkle will be honored for their 

development of Texture Based Engineering Tools at the 

R&D 100 Awards Banquet, Oct. 19, in the Grand Ballroom 

of Chicago’s Navy Pier. Their TBET technology will be 

among the 2006 R&D100 winners featured in the September issue of R&D Magazine.

Bryden says one of the best things about winning an 

R&D100 Award is that it spreads the word about virtual 

engineering and helps people better understand the 

process.

Bryden, Bivins and McCorkle 

Win 2006 R&D100 Award

Q

A

Present at Birth: The award-winning Texture Based Engineering 

Tools, TBET, allows Doug McCorkle (left) and Gerrick Bivins to enter 

a virtual environment that displays velocity information from a data 

set about the birth of a star.

(left to right) Doug McCorkle, Mark Bryden and Gerrick Bivins.

Award brings 

Ames Lab’s total 

to a “Sweet16”

BY SAREN JOHNSTON
4 INQUIRY 2006

EEPING COMPUTER FILES PRIVATE REQUIRES 

only the use of a simple encryption program. 

For criminals or terrorists wanting to conceal 

their activities, however, attaching an encrypted 

file to an e-mail message is sure to raise 

suspicion with law-enforcement or government agents 

monitoring e-mail traffic.

But what if files could be hidden within the complex 

digital code of a photographic image? A family snapshot, 

for example, could contain secret information, and even a 

trained eye wouldn’t know the difference.

That ability to hide files within another file, called 

steganography, is here thanks to a number of software 

programs now on the market. The emerging science of 

detecting such files – steganalysis – is getting a boost 

from the Midwest Forensics Resource Center and a pair 

of Iowa State University researchers.

Payloads and JPEGs

Electronic images, such as JPEG files, provide the 

perfect “cover” because they’re very common – a single 

computer can contain thousands of JPEG images, and 

they can be posted on Web sites or e-mailed anywhere. 

Steganographic, or stego, techniques allow users to 

embed a secret file, or payload, by shifting the color 

values just slightly to account for the “bits” of data being 

hidden. The payload files can be almost anything from 

illegal financial transactions and the proverbial off-shore 

account information to terrorist-cell communications or 

child pornography.

“We’re taking very simple stego techniques and trying 

to find statistical measures that we can use to distinguish 

an innocent image from one that has hidden data,” says 

Clifford Bergman, an ISU math professor and a researcher on the project. “One of the reasons we’re focusing on 

images is there’s lots of ‘room’ within digital images to 

hide data. You can fiddle with them quite a bit, and visually a person can’t see the difference.”

“At the simplest level, consider a black and white 

photo – each pixel has a grayscale value between zero 

(black) and 255 (white),” says Jennifer Davidson, an ISU 

math professor and the other investigator on the project. 

“So the data file for that photo is one long string of those 

grayscale numbers that represent each pixel.”

Encrypted payload files can be represented by a string 

of zeros and ones. To embed the payload file, the stego 

program compares the payload file’s string of zeros and 

ones to the string of pixel values in the image file. The 

stego program then changes the image’s pixel values so 

that an even pixel value represents a zero in the payload 

string and an odd pixel value represents a one. The person receiving the stego image then looks at the even-odd 

string of pixel values to reconstruct the payload’s data 

string of zeros and ones, which can then be decrypted to 

retrieve the secret file.

“Visually, you won’t see any difference between the 

before and after photo,” Davidson says, “because the 

shift in pixel value is so minor. However, it will change 

the statistical properties of the pixel values of the image, 

and that’s what we’re studying.” 

Artificial intelligence

Given the vast number of potential images to review and the variety and complexity of the embedding 

K

BY KERRY GIBSON

Researchers detect secret files in lurking within digital images

Seemingly innocent images can be used to hide other computer 

data by using steganography programs that replace bits of information in the original image with encrypted data from the payload file.

Plain Sight Plain Sight
INQUIRY 2006 5

algorithms used, developing a quick and easy technique to 

review and detect images that contain hidden files is vital. 

Bergman and Davidson are utilizing a pattern-recognition 

system called an artificial neural net, or ANN, to distinguish between innocent images and stego images.

Training the ANN involved obtaining a database of 

1,300 “clean” original images from a colleague, Ed Delp, 

at Purdue University. These images were then altered 

in eight different ways using different stego embedding 

techniques – involving sophisticated transfer techniques 

between the spatial and wavelet domains – to create a 

database of over 10,000 images.

Once trained, the ANN can then apply its rules to new 

candidate images and classify them as either innocent or 

stego images.

“The ANN establishes kind of a threshold value,” Bergman says. “If it falls above the threshold, it’s suspicious.

“If you can detect there’s something there, and better 

yet, what method was used to embed it, you could extract the encrypted data,” Bergman continues. “But then 

you’re faced with a whole new problem of decrypting the 

data ... and there are ciphers out there that are essentially impossible to solve using current methods.”

In preliminary tests, the ANN was able to identify 92 

percent of the stego images and flagged only 10 percent 

of the innocent images, and the researchers hope those 

results will get even better. An investigator with the Iowa 

Department of Criminal Investigation is currently fieldtesting the program to help evaluate its usefulness, and a 

graphical user interface has been developed to make the 

program more user-friendly.

“Hopefully we can come up with algorithms that are 

strong enough and the statistics are convincing enough 

for forensic scientists to use in a court of law,” Bergman 

says, “so they can say, ‘There’s clearly something suspicious here,’ similar to the way they use DNA evidence to 

establish a link between the defendant and the crime.”

The Midwest Forensics Resource Center, operated 

by Ames Laboratory and Iowa State University, provides 

research and support services to crime laboratories and 

forensic scientists throughout the Midwest.

For more information:

Clifford Bergman, (515) 294-8137

cbergman@iastate.edu

Jennifer Davidson, (515) 294-2941

davidson@iastate.edu

Research funded by:

Midwest Forensics Resource Center

National Institute of Justice

Jennifer Davidson

Q

The images shown opposite and above represent how ever-increasing amounts of the payload 

file — the fighter jet — are embedded in the original image. In actual use, the changes in the 

original image are so subtle that it’s impossible to tell that the image has been altered.

Clifford Bergman
The Computational Chemistry “Toolbox”

OU NEED THE RIGHT TOOLS FOR THE 

job at hand. It’s a familiar phrase. We hear 

some version of it every day in all forms of 

advertising, from newspaper ads to television commercials to unwanted e-mails. The 

sales pitch is a popular one, mostly because the reality is 

pretty much undeniable: using the appropriate tools for 

a specific task almost always results in time-, energy- and 

cost-savings.

No need to tell this to Mark Gordon – you’d be preaching to the choir. Gordon, director of Ames Laboratory’s 

Applied Mathematics and Computational Sciences program and an Iowa State University Distinguished Professor 

of chemistry, has devoted much of his career to making 

sure the right tools are available in GAMESS, the “toolbox” 

that he and thousands of researchers worldwide use on a 

daily basis to learn more about the goings-on of molecules and atoms – how they act, interact and react.

GAMESS, or the General Atomic and Molecular Electronic Structure System, is a software suite chock-full of 

quantum chemistry codes and functionalities – the tools 

that significantly enhance efforts focused on finding solutions to problems involving molecular processes, such as 

designing new fuels and gaining better insights into combustion, catalysis and photochemical energy conversion.

Gordon fosters the development of GAMESS and 

its software tools, which continue to grow and 

diversify as a result of his contributions to the 

suite and those of many other “code crafters,” 

including Gordon’s co-worker, Ames Lab associate Mike Schmidt, various current and past members 

of the Gordon research group, and numerous professional 

colleagues.

The GAMESS software tools are designed to take 

advantage of parallel, high-performance supercomputing 

systems that are capable of doing trillions of calculations 

per second. On such systems, the versatile software suite 

can perform the very highest levels of theory for modeling 

complex physical, chemical and biological systems. The 

continued enhancements Gordon and his colleagues make 

to GAMESS dramatically improve the ability to do such 

high-end and accurate calculations, a feat that at first glance 

may seem to impact only a select few. However, Gordon 

promptly rejects this all-too-quick assumption.

“If you have something that’s the highest level of 

theory you can do, and you make that better in some 

way – faster, more convenient, more accurate – that has 

an impact on your ability to say, ‘We’ve nailed this now, 

and now other people can use this as a benchmark for 

simpler methods,’ ” explains Gordon. 

Turning sophisticated theory 

into scalable code Y BY SAREN JOHNSTON
INQUIRY 2006 7

Adding water to the tool “pool”

Making a good tool even better, Gordon 

led a team that included his postdoctoral 

research associate, Hui Li; former graduate 

student Jan Jenson, now at the University of 

Iowa; Fedorov; and Kitaura in developing a 

method of modeling the activity of molecules in solution. They created the new 

GAMESS tool by interfacing the Polarizable 

Continuum Model, PCM, with the FMO 

method. “If you’re interested in polymers 

and enzymes, whatever they do, they do 

in solution, usually in aqueous solution,” 

says Gordon. “That means just doing FMO 

calculations is not enough – you need to 

get the solvent in there.” Expanding, he 

says, “If you imagine a solvent and throw 

in something like a protein, the protein sort 

of sweeps out a volume. We’re not looking 

at individual water molecules now – we’re 

representing the whole solvent sort of as 

a sea.” Offering an analogy, he continues, 

“It’s exactly as if you went swimming. You 

don’t see the individual water molecules; 

you see the whole ocean. So that’s the 

nature of this type of method, and we have 

a very nice one in GAMESS.”

A tool of prediction

A GAMESS tool that has been around since 1990 and 

continues to be improved upon is the Effective Fragment 

Potential, or EFP. When scientists deal with systems 

containing so many atoms that quantum mechanics 

can’t be done, even at simple levels, the EFP method 

offers an alternative means. By combining the EFP with 

quantum mechanics in a way that a quantum mechanical 

description is produced only for that portion of a system 

that is going through a chemical change, scientists can 

then approximate the remainder of the system based 

on that fragment of information. The entire calculation 

takes orders of magnitude less time than a fully quantum 

calculation.

“The effective fragment potential is becoming more 

and more exciting as we try to model the interactions 

between molecules,” says Gordon of the method that 

he and Jan Jenson developed in collaboration with Dr. 

Walter Stevens at the National Institute of Standards and 

Technology. 

 “This time we do care about each water molecule 

or each solvent molecule,” Gordon notes. “Molecules 

interact with each other in a variety of different ways, and 

some of those interactions are easier to derive models for 

than others.”

Some molecular interactions that are not so easy to 

model are those associated with dispersion and charged 

“Toning up” the toolbox

Helping advance the capability to do top-notch theory 

is an enhancement to the GAMESS toolbox that combines 

the Fragment Molecular Orbital, or FMO, method of handling large molecular systems quantum mechanically with 

the Polarizable Continuum Model, or PCM, for solvent 

computations. Now that’s a lot of technical talk, so let’s 

see if we can break it down.

Interestingly, breaking it down is exactly the idea behind the FMO portion of this combination tool. Gordon 

explains, “What you’d like to do, in principle, is take the 

highest level of theory you can do and apply it to a big 

molecule, such as a polymer, enzyme or protein. The 

problem is that to do quantum chemistry on something 

that big is hugely expensive computationally, especially 

if you want to do a level of theory that is very demanding. The FMO method offers a way of ‘chopping’ a very 

large molecule into relatively small pieces by doing explicit 

calculations on monomers, the repeat units in a polymer, and dimers, which are two monomers. Some very 

clever methods are then used to put all those fragments 

together to make the larger system.”

But how good is the piecing together of fragments 

relative to doing the full calculation if you could do the full 

calculation? Gordon says test calculations can be done on 

small molecules in which the full calculations can be accomplished without any approximation. These calculations 

can then be compared to those derived from the molecule’s FMO. “The errors are within what most people call 

chemical accuracy,” he notes. “The way to think about this 

is if an experimentalist had error bars, then the accuracy 

would be within those error bars and would never impact 

the experiment. And that’s pretty good!”

Gordon credits his former graduate student, Dimitri 

Fedorov and his colleague Kazuo Kitaura, both of the 

Japanese National Computational Laboratory, AIST, for developing the FMO method for the GAMESS software suite. 

“The FMO method has been implemented for five different levels of theory, from the very lowest level of quantum 

chemistry theory that we do to the very highest,” he says. 

“Fedorov and Kitaura are interested in biomolecules, so 

they’ve done calculations on systems with as many as 

20,000 atoms, which is unheard of in quantum chemistry. You’re lucky if you can do 100 atoms with quantum 

chemistry, so this is orders of magnitude larger than what 

people can usually do.”

“There is a great satisfaction 

in building good tools for 

other people to use.”

 ~FREEMAN DYSON,

 English-born American physicist and mathematician

Mark Gordon
8 INQUIRY 2006

This image is a molecular dynamics simulation of an ionic liquid composed of 512 ions. There are 256 positively charged 

ions (1,2,4-triazolium) and 256 negatively charged ions 

(dinitramide). The simulation was done on a 16-CPU parallel 

machine using the new GAMESS effective fragment potential 

code. The CPU time efficiency was 96 percent – testimony to 

the efficiency of the innovative GAMESS tool.

species. Nonetheless, Gordon and his group members 

have added those capabilities to GAMESS in the past year.

Dispersion

Dispersion is one means by which molecules exert 

forces on one another. Dispersion forces are randomly 

and spontaneously generated continuously over the entire 

molecule, making them extremely difficult to model. 

However, Ivana Adamovic, a former Gordon group 

member now at the Harvard School of Health in Boston, 

took on the challenge, developing a model potential for 

GAMESS that handles this fleeting molecular ebb and 

flow. Thanks to her contribution, the Gordon group has 

been able to use the new GAMESS tool to do calculations 

on DNA base pairs, and they are currently working with 

the ISU chemical engineering department to study the 

aggregation of polymers, such as latex.

Charge transfer interactions

Charge transfer interactions are those that occur 

between ions. Ionic bonds are formed when the relationship between two atoms or molecules is such that one 

of them has a far greater ability to attract electrons and 

“steals” an electron from the other so that the now oppositely charged ions are attracted.

Hui Li, who will be an assistant professor at the University of Nebraska in the fall of 2006, and Heather Netzloff, a 

former graduate student of Gordon’s now at Australian National University, enhanced the EFP method for GAMESS 

by respectively creating a molecular dynamics code to 

address the interactions that occur between ions and optimizing the code to take advantage of parallel computers.

The addition of the charge transfer code to the 

GAMESS toolbox is of particular importance to Gordon 

who is interested in ionic liquids in the design of highenergy fuels — products that bring together positively and 

negatively charged species. “You can’t simulate those 

relationships adequately unless you have something that 

accounts for the charge transfer interactions, and we now 

have in GAMESS a molecular dynamics code that allows 

us to do that thanks to Hui and Heather,” says Gordon.

The “tool” de force

“GAMESS runs on every kind of computer platform and 

compiler you can imagine,” says Gordon. “It just passed 

20,000 registered user groups in over 100 countries. 

This translates into an estimated 100,000 to 150,000 

individual users. They range from people in academics to 

industry to government labs.”

GAMESS is distributed at no cost to users by accessing 

www.msg.ameslab.gov and signing a license agreement.

Q

For more information:

Mark Gordon, (515) 294-0425

gordon@ameslab.gov

Research funded by:

U.S. Department of Defense

U.S. Department of Energy, Scientific

 Discovery through Advanced Computing 

MacMolPlt, a GAMESS tool developed by Ames Lab associate 

scientist Brett Bode, makes it possible to visualize the results 

of GAMESS calculations on Macintosh computers. The above 

MacMolPlt image is of a mesoporous silica nanopore. Mesoporous silica materials hold great promise for the design of a 

new generation of highly efficient and selective catalysts.
INQUIRY 2006 9

historic scientific achievement to the 

future of optical technology. The 

Ames Lab and Iowa State University 

are indeed proud of the pivotal role 

played by Professor Soukoulis.”

Accepting the Descartes Prize, 

Soukoulis paid tribute to the organizations that have supported his 

research on LHMs. “I would like 

to express my gratitude to Ames 

Laboratory and Iowa State University 

for accommodating my teaching 

duties to allow me to also pursue 

research on left-handed materials 

in Europe,” he said. “I would like 

to thank the U.S. Department of 

Energy for their support during the 

last 20 years. Our Ames Laboratory 

work on photonic crystals led to the 

field of negative index materials and 

metamaterials.”

The Descartes Prize for Excellence in Scientific Research, now in 

its sixth year, recognizes outstanding 

scientific and technological results 

achieved through international 

collaborative research in diverse 

disciplines. Winners are selected by 

a grand jury of experts in science, 

industry and the general public.

OSTAS SOUKOULIS,

an Ames Laboratory 

senior physicist and an 

Iowa State University 

Distinguished Professor of physics and astronomy, 

coordinates the research team that 

won the 2005 Descartes Prize for 

Excellence in Scientific Collaborative Research, the European Union’s 

highest honor in the field of science. 

He and his collaborators received 

the prestigious award for creating 

a novel class of artificial metamaterials called left-handed materials, 

or LHMs, which exhibit fascinating 

properties that cannot be found in 

naturally occurring materials.

LHMs exhibit negative refraction, 

bending light in the opposite direction to that seen in natural materials. They can be fabricated to have 

zero reflectance for all angles hit by 

incoming electromagnetic waves. In 

addition, they can focus light without the need for curved surfaces. 

These and other amazing properties 

promise a wide range of potential 

applications for LHMs.

Soukoulis, who has also been an 

associate with the research center 

FORTH, in Crete, Greece, since 

1984, said he was lucky to work 

with a top-notch team of international researchers in creating the 

new subclass of materials. The 

team includes Professor Sir John 

Pendry, Imperial College, UK; Professor Ekmel Ozbay, Bilkent University, 

Turkey; Professor Martin Wegener, 

University of Karlsruhe, Germany; 

Professor David Smith, Duke University, USA; and Professor E. N. 

Economou and Dr. Maria Kafesaki, 

both from FORTH and the University 

of Crete.

The research team was awarded 

the Descartes Prize for Research in 

Physics at a ceremony held at the 

Royal Society in London on Dec. 

2, 2005. The team received prize 

money of 1 million euros (about 

$1.3 million) for their winning project, 

“Extending Electromagnetism through 

Novel Artificial Materials, or “EXEL.”

“Our EXEL team was able to 

demonstrate the experimental reality 

of LHMs and their consistency with 

the laws of physics,” said Soukoulis. 

“This realization opened up the possibility of unprecedented applications and devices.”

The team has already shown 

how the ability to focus radio waves 

could lead to smaller, better-performing magnetic resonance imaging machines for medical diagnostics. Numerous applications in the 

cellular communications industry are 

also envisioned, including antennas 

and waveguides that are 100 times 

smaller and much lighter than those 

of today. Even slight improvements 

to these types of devices can make 

a significant financial impact.

Ames Laboratory Director Tom 

Barton praised the work of Soukoulis 

and the EXEL team, saying, “It probably would be difficult to overstate 

the potential importance of this 

Costas Soukoulis Wins European 

Union’s Highest Science Prize

C Costas Soukoulis accepts the 2005 Descartes Prize 

for Excellence in Scientific Collaborative Research 

at the Royal Society in London on Dec. 2. Members 

of the winning collaborative team are, left to right: 

Stephan Linden (University of Karlsruhe), Mike Wiltshire (Imperial College), Maria Kafesaki (FORTH), 

David Smith (Duke University), Martin Wegener 

(University of Karlsruhe), Ekmel Ozbay (Bilkent University), and Sir John Pendry (Imperial College). 

Q

Costas Soukoulis

BY SAREN JOHNSTON
10 INQUIRY 2006

Shiny glue

Solder is the shiny metallic “glue” that holds components on circuit boards and bonds other electrical connections. Though a computer’s circuit boards contain only 

small amounts of lead solder, the problem is overall volume. By some estimates, about 3,000 tons of electronic 

waste is discarded daily just in the United States.

Composed of lead and tin, traditional solder melts and 

flows easily, but sets up quickly to create a strong, durable 

bond between the mating surfaces. A solder blend of 63 

percent tin and 37 percent lead results in a eutectic alloy 

– one that acts like a pure metal with a single melting (and 

solidification) point.

“Finding a substitute for lead that gave the solder similar 

properties was difficult,” says Ames Laboratory senior metallurgist Iver Anderson. “With our basic understanding of 

alloys, we developed a tin-silver-copper alloy that offered a 

lower melting temperature and greater strength than other 

lead-free alternatives being considered.”

Big bucks

The Ames Laboratory’s solder technology was patented in 1996, and nearly 60 companies worldwide have 

licensed Ames Lab’s lead-free solder, according to Ken 

Lead-free solder licensed worldwide 

as EU lead-free rules take effect

EAD HAS LONG BEEN RECOGNIZED AS A

highly toxic material that can cause brain damage. 

Its use in paint was banned in 1978, and it was later 

removed from gasoline to further protect human 

health. But a burgeoning source – electronic 

waste – poses a substantial new threat to the environment 

as lead and other chemicals leach from computers, cell 

phones and other electronic devices being buried in landfills.

Effective July 1, the European Union began strictly 

limiting the amount of lead and other hazardous materials 

lurking within the circuitry of any electronic appliance sold.1

Given the global nature of the electronics industry, however, 

the European ban is in essence international in scope. 

As electronics and appliance manufacturers scrambled 

to meet those tough new restrictions, a lead-free solder 

developed several years ago at Ames Laboratory played a 

key role.

L

BY KERRY GIBSON

Lead-free Europe

Thanks to Ames Lab Innovation
INQUIRY 2006 11

Kirkland, executive director of the Iowa State University 

Research Foundation. To date, those licenses have generated royalties in excess of $7 million. ISURF holds the 

patents for research developed at Iowa State, including 

Ames Laboratory.

“With the European directives and a similar commercial 

initiative in Japan, we’ve seen a growing interest in the 

alloy,” Kirkland says. “The technology was a little ahead of 

its time, but it’s an excellent product and we have a strong 

patent; you can’t ask for a better combination than that.”

The Ames Lab solder is just one of several lead-free 

alternatives on the market. The type and specific composition of lead-free solder also depends on the soldering 

technique used and the end application. In addition to the 

tin-silver-copper alloy, Anderson’s group developed modified alloys that also contain iron, cobalt and other similar 

elements. These blends are suitable for higher-temperature 

applications and have also been patented by ISURF.

Battling brittleness

One ongoing problem with lead-free alternatives now 

available is their tendency to get brittle over time after repeated or prolonged heating cycles. And heat has become 

a growing factor as technological advances have boosted 

operating temperatures. For example, the steady climb in 

computer processor speeds has meant a corresponding increase in the amount of heat they generate. And computers aren’t the only devices that generate heat.

“Even the circuitry in your cell phone operates at about 

125 degrees Celsius,” Anderson says, “and over six months’ 

use, that can mean several hundred hours of high temperatures. If you drop it now, the solder joints have become 

more brittle and the risk of it ‘breaking’ is higher.”

To combat this solder “aging” problem, Anderson’s 

group has recently been studying more additives to the 

tin-silver-copper formula, including silicon, titanium, chromium, manganese, nickel, zinc and germanium. Joints 

soldered with the different alloys were subjected to150 C 

for1,000 hours, then tested for both shear strength and 

impact strength.

“Zinc appears to be most attractive in terms of retained 

ductility and strength,” Anderson says, “and also offers 

benefits in terms of solderability, ease of alloying and material cost.” While additional testing is needed, he adds that 

the tin-silver-copper-zinc composition is covered under the 

original patent.

Added bonus

One other benefit of this recent work is development of 

a simple technique for characterizing the bulk composition 

of solder joints using an electron microprobe. This permits 

Anderson’s research team to analyze the new compositions 

being studied under different soldering conditions.

“With the elimination of lead, tin-silver-copper solders 

are here for the long run,” Anderson says. “But that 

doesn’t mean we’ll stop trying to improve our basic understanding of how these alloys work in order to improve 

their performance.”

1

 –The Waste Electrical and Electronic Equipment directive and the 

Restriction of Hazardous Substances directive.

For more information:

Iver Anderson, (515) 294-9791

andersoni@ameslab.gov

Research funded by:

DOE Office of Basic Energy Sciences,

 Materials Science and 

 Engineering Division

Q
12 INQUIRY 2006
from the

Out

INQUIRY 2006 13

N THE 1966 SCIENCE-FICTION

blockbuster, “Fantastic Voyage,” a 

small submarine and its medical 

crew are miniaturized to microscopic size and injected into the 

body of a dying scientist. They journey 

through the man’s body to remove a 

blood clot in his brain. 

Fast forward 40 years. In a somewhat similar plot line, Ames Lab chemist Victor Lin has found a way to use 

nanoscale “capsules” to deliver a dose 

of chemotherapy drugs to specific cancer cells without the risk of side affects 

to healthy cells.

Using tiny silica particles called 

mesoporous nanospheres to carry 

drugs inside living cells, Lin is studying different methods to control 

whether the particle delivers its 

pharmaceutical payload.

“First, the nanospheres are only 

about 200 nanometers in diameter, 

roughly the size of a virus, so they 

won’t trigger an immune response 

in the body,” Lin says. “They’re also 

biocompatible so they can be readily 

absorbed by the cells.”

But it’s the structure of the nanospheres that makes drug delivery possible. The spheres have thousands of 

parallel channels running completely 

through them. Through capillary action, the spheres can soak up molecules of the drug to be delivered. 

When the channels are filled, the 

ends of the channels are “capped” to 

safely seal the drug inside. Once the 

caps are in place, the nanospheres 

are “washed” to remove the drug 

from the outer surface.

Controllable caps

The type of material used for the 

end caps, how they’re held in place 

and how they’re released is the 

focus of Lin’s work. The caps can be 

dendrimers, biodegradable polymers, 

genes, proteins, metallic nanoparticles 

or semiconductor nanocrystals – also 

known as quantum dots – and are 

held in place by chemical bonds. 

Cellular Drug Delivery

Mesoporous silica 

nanospheres are the focus I of Victor Lin’s research

Inside

BY KERRY GIBSON

(left) Living human cervical cancer cells containing mesoporous silica nanospheres 

capped with iron-oxide nanoparticles are drawn through solution toward a small 

rare-earth magnet placed beside the vial. 
14 INQUIRY 2006

Once the nanospheres are inside the 

target cells, a trigger is used to pop the 

caps off and release the drug. 

“We’re looking at two levels 

of control,” Lin says of the trigger 

mechanism. “One level is to have the 

cell control the release and the other 

would be to control the release externally.” Lin explains that the chemicalbond holding the cap in place can be 

engineered to be unphased by chemicals present in normal cells. However, 

in cancer cells these chemicals, such 

as antioxidants, appear in much higher 

concentrations and would break the 

bonds on the caps and release the 

drugs. In this way, only cancer cells 

could be targeted with powerful 

chemotherapy drugs, such as Taxol or 

doxorubicin, while the nanospheres 

inside the normal cells would remain 

capped and not cause unwanted side 

affects by damaging healthy cells.

To achieve external control, Lin is 

using iron-oxide nanoparticle caps 

that can be manipulated by a magnetic field. In a simple demonstration 

of the principle, Lin holds a small 

rare-earth magnet up to a liquid-filled 

glass vial containing human cervical 

cancer cells grown in vitro that contain 

nanospheres capped with iron-oxide 

particles. The cells slowly migrate and 

cluster to the side of the vial next to 

the magnet. 

“By using a powerful magnet, we 

can first concentrate the nanospheres 

at a particular point, such as a tumor 

site, and then use the magnetic field 

to remove the caps and release the 

drug,” Lin says. “The advantage of 

using a magnetic trigger as opposed to 

an ultraviolet light trigger is that there’s 

no limit to the depth of tissue we are 

able to probe — think of an MRI.”

Other possibilities

Beyond the possibilities for 

intercellular drug delivery, the nanospheres may provide the key to 

studying what takes place within a 

cell. Currently, scientists have difficulty introducing chemicals or genes 

into cells without either damaging 

the cell or causing a chain reaction of 

events that can’t be tracked.

“With current gene therapy, it’s 

possible to switch genes on and off, 

but you don’t really know if you are 

affecting other parts and processes of 

the cell as well,” Lin says. “You may 

be able to get a plant cell to produce 

a certain desired product, but the 

yield may drop significantly.” By using 

externally controlled nanospheres, Lin 

explains that it may be possible to 

sequentially release genes, chemical 

markers and other materials within 

cells in order to track what happens 

and what specific changes take place. 

This phase of Lin’s research ties into 

a larger plant metabolomics project 

at Ames Laboratory being undertaken 

by senior chemist and Chemical and 

Biological Sciences Program Director, 

Ed Yeung.

For more information:

Victor Lin, (515) 294-3135

vsylin@iastate.edu

Research funded by:

National Science Foundation

DOE Office of Basic Energy Sciences,

 Chemical Sciences Division

Q

By manipulating the magnetic field, the caps “pop” free, 

releasing the drug. 

Victor Lin 

This diagram shows how the iron-oxide caps hold the 

drugs within the channels in the nanospheres. 

drug payload
MILESTONES

INQUIRY 2006 15

Symposium honors Ames 

Lab’s “Dr. Rare Earth”

Scientific excellence. Exemplary 

researcher. Prolific writer. Significant 

contributor. Colleague, mentor and 

friend. Wonderful human being! 

These were just some of the phrases 

used by speakers and colleagues 

to describe Ames Laboratory senior 

metallurgist Karl Gschneidner, Jr. during a symposium bearing his name. 

The event, held Nov. 14, 2005, 

honored Gschneidner’s 53 years 

of service to the rare earth, materials and physics communities, and 

celebrated his 75th birthday. 

Entitled “Materials and Physics: Life 

on Earth With and Without the Rare 

Earths,” the symposium brought some 

of the top researchers from around 

the world to share their expertise. 

Sponsored jointly by Ames Laboratory and the Iowa State University 

department of materials science and 

engineering, the event was also one 

of several activities planned to observe 

100 years of ceramics/materials science and engineering at Iowa State.

Ames Lab senior scientist Vitalij 

Pecharsky, who helped organize the 

symposium, kicked off the event with 

a short tribute to his close colleague.

“It’s been my privilege to know 

Karl for the last 16 years,” Pecharsky 

said. “He is one of the finest human 

beings I have ever known in my life, 

and it’s been a pleasure organizing 

this symposium. It’s a fitting way to 

recognize what Karl has done, not only 

for this community, but for scientists 

throughout this country and 

around the world.” 

Ames Lab Director Tom 

Barton shared a letter from 

DOE Office of Science Director Ray Orbach, who congratulated Gschneidner on 

his 53 years of “prolific and 

dedicated service to the rare 

earth community. This (symposium) is a most fitting way 

to acknowledge someone 

whose expertise is so recognized and respected that the 

scientific community regards 

you as ‘Mr. Rare Earth.’ ”

Adding his own congratulations, Barton said, “I’d like 

to say happy birthday and a 

very sincere thank you for the 

tremendous contributions 

that you have made to the 

scientific, international reputation of the Ames Laboratory. You’ve certainly earned 

the nickname, but I think we 

ought to at least promote 

you to ‘Dr. Rare Earth.’ ” 

“On a personal note, Karl, 

your infectious enthusiasm for, and 

your obvious, genuine enjoyment of, 

your science has always served as a 

constant reminder to me that great 

science is great fun,” Barton added.

Reflecting on his symposium, Gschneidner thanked the organizers and 

the presenters.

“The quality of the presentations 

was so outstanding, I actually stayed 

awake through all of them,” he said 

with a characteristic twinkle in his eye.

Chemist John 

Corbett turns 80

On Thursday, March 

23, 2006, Ames Laboratory senior chemist John 

Corbett turned 80, and the 

occasion did not go unnoticed 

by his friends and co-workers at 

Ames Lab. A birthday celebration, 

complete with cake, was held to 

observe the milestone for the 

man who has been a member of 

Ames Laboratory’s research team 

for 53 years.

Corbett, who is still actively 

involved in research, is also an Iowa 

State University Distinguished Professor of Liberal Arts and Sciences, has 

served as chair of the chemistry 

department and as division chief and 

program director in the Ames Laboratory. He is a Fellow of the American Association for the Advancement 

of Science. Among his honors are 

the ACS Awards in Inorganic Chemistry and in Distinguished Service 

in the Advancement of Inorganic 

Chemistry, a Senior Scientist Award 

from the A.V. Humboldt Foundation, 

two DOE Awards for Outstanding 

Scientific Accomplishments in Sustained Research in Materials Chemistry, and election to the National 

Academy of Sciences. 

To honor Corbett, Ames Laboratory Director Tom Barton presented 

the longtime researcher with a 

plaque bearing the following inscription: “To John Dudley Corbett on the 

occasion of your 80th birthday, we 

take the opportunity to thank you for 

the luster that your scientific achievements have brought upon the Ames 

Lab and Iowa State University.”
manner. In contrast, the Fenton reaction plays not-so-benign roles in the biology of aging and disease, contributing 

to certain types of DNA damage that may not self-repair 

and, so, accumulate with age.

Closing in on the chemistry

“Knowing the nature of the intermediate is crucial 

to understanding the role of Fenton chemistry in issues 

related to environmental and atmospheric chemistry, as 

well as human health and aging,” says Bakac, who is also 

an Iowa State University adjunct professor of chemistry. 

“The fact that we have now eliminated iron(IV) in Fenton 

reaction and confirmed it in ozone reaction, may provide a 

foundation for the development of new and useful catalytic 

reactions based on iron(IV).”

Ames Lab’s basic research effort was done in collaboration with Carnegie Mellon University in Pittsburgh and the 

University of Minnesota in Minneapolis. An article by the 

collaborating scientists describing their research and its indisputable results was published in Angewandte Chemie. The 

journal gave the article a “Very Important Paper,” or VIP, rating, which less than 5 percent of their manuscripts receive.

As with many scientific achievements, the work done by 

Bakac and Pestovsky that eventually ruled out iron(IV) as 

the Fenton intermediate did not initially have that goal. “We 

started out studying aqueous iron(IV) for several reasons,” 

says Bakac. “It is a very unusual species, but in stabilizing 

biological environments, iron(IV) has been found to play a 

role, especially in enzymatic reactions. And as soon as you 

find something that is considered unusual to actually function in real life, you know it’s not that uncommon – it just 

hasn’t been recognized before.”

Andreja’s idea

“Iron(IV) was not a totally unknown species when we 

started looking at it,” says Bakac. A research group in Denmark had done the reaction of iron(II) with ozone and proposed that iron(IV) was produced,” she explains. “That was 

about a decade ago, and the work kind of went unnoticed.” 

While reviewing the literature relating to iron(IV), Bakac 

came across the Danish papers again. “As I read those 

papers, I figured if that was iron(IV), then there ought to be 

much more chemistry there, some of it potentially important in both catalytic and biological contexts,” she says. “Of 

course, nobody knew whether iron(IV) was really involved. 

It was some sort of intermediate that hadn’t been characterized. This is where Oleg and I got involved.”

Bakac and Pestovsky set out to generate this species 

from iron(II) and ozone, and look at its chemistry. “All 

along we were hoping to find that this really was aqueous 

iron(IV), a simple, but probably extremely reactive species,” 

OR MORE THAN 100 YEARS, CHEMISTS 

debated the nature of the mechanism that 

triggers the Fenton reaction, one of the most 

powerful oxidizing reactions available for breaking 

apart organic compounds. Back and forth the 

controversy persisted, generating a profusion of professional articles that supported either one or the other of the 

likely candidates – short-lived, difficult-to-measure hydroxyl 

radicals or the extremely rare iron(IV). Which one was the 

highly reactive Fenton intermediate that could initiate the 

oxidations of countless substances, from biomolecules, 

such as proteins, sugars, fatty acids and nucleic acids to the 

pollutants found in smog and industrial wastes?

Decades passed, and the identity of the elusive Fenton 

intermediate remained a mystery. Now, however, Ames 

Lab senior chemist Andreja Bakac and assistant chemist 

Oleg Pestovsky have generated, characterized and ruled 

out iron(IV) as the Fenton intermediate. Their irrefutable 

research results tip the balance heavily toward hydroxyl 

radicals, or OH radicals, as the crucial intermediate by 

which the Fenton reaction proceeds to completion.

Fenton facts

Discovered in 1894 by H. J. H. Fenton, the Fenton reaction is the oxidation of aqueous iron(II), or Fe(II), with hydrogen peroxide, a versatile, safe and effective oxidant. (An 

oxidant is a substance containing oxygen that reacts chemically with other materials to produce new substances.) 

The pervasive nature of the Fenton reaction accounts 

for scientists’ longstanding efforts to unravel the centuryold mystery surrounding the famous Fenton intermediate that allows the reaction to proceed to completion. 

And no wonder – the reaction 

operates or is employed almost 

everywhere, with both good and 

not-so-good effects. It’s critical in the treatment of organic 

pollutants that are introduced 

into the environment by the 

uncontrolled use of such things 

as pesticides and herbicides, 

among many other man-made 

contaminants. It’s vital within the 

industrial chemistry arena, where 

researchers investigate catalysts 

with the goal of making various 

chemical processes go faster and 

in a more selective and efficient 

F

(left) Bakac and Pestovsky bubble ozone through a solution and use it to generate Fe(IV).

BY SAREN JOHNSTON

“Radical” Means

Researchers solve century-old 

chemistry conundrum

16 INQUIRY 2006
INQUIRY 2006 17

(left) Preserving a life: Andreja Bakac demonstrates the device that allows 

her and Oleg Pestovsky to generate and freeze iron(IV) in less than a second.

(right) Very “cool” stuff: A delicate spray of newly generated iron(IV) has 

frozen instantly to the inner walls of this copper cylinder that has been cooled 

to liquid-nitrogen temperature (77 Kelvin, or minus 321 degrees Fahrenheit).

Bakac says. “The initial reactivity data were truly exciting 

and consistent with an iron(IV) species, but still we had no 

proof,” she adds.

Mössbauer “magic”

“We saw some beautiful chemistry, but we definitely 

needed to identify this species,” says Bakac, “so we got 

in touch with Eckard Münck at Carnegie Mellon. He’s the 

world expert in Mössbauer spectroscopy, which is considered to be the most definite of spectroscopic methods 

when working with iron.” 

Bakac explains that iron(IV) is a short-lived species, 

lasting about 10 seconds at room temperature. Although 

that is orders of magnitude more than some intermediates 

she works with that live only milliseconds or microseconds, 

Bakac notes that the 10-second life of iron(IV) did present 

a problem. “It was a lot to deal with when we were producing the material here in Ames and the group that was 

analyzing it was in Pittsburgh,” she says. Fortunately, the 

two research teams collaborated and found a way to get a 

sample from Ames to Pittsburgh before it “died.” 

“We designed and built a device that allows us to generate iron(IV) and immediately cool it down to liquid nitrogen temperature and freeze it in a fraction of a second,” 

says Bakac. “We then packed the solid into a liquid-nitrogen-cooled dewar and shipped it overnight to Pittsburgh. 

There, the Carnegie Mellon team collected the Mössbauer 

spectrum at liquid helium temperature.” 

Mössbauer studies of the Ames samples done under 

Münck’s direction by Carnegie Mellon research associate Emile Bominaar and graduate student Sebastian 

Stoian proved the intermediate generated by Bakac and 

Pestovsky was exactly what they were hoping for – the 

iron(IV) species.

In addition to the Carnegie Mellon work, contributions 

by Lawrence Que and his postdoctoral associate Xiaopeng 

Shan at the University of Minnesota further confirmed 

the iron(IV) species. “They took our sample to Stanford 

University to get an X-ray absorption spectrum, or XAS, and 

that spectrum was consistent with the oxidation state of 

iron(IV),” says Bakac.

The Mössbauer and XAS analyses, combined with all 

the chemistry carried out at Ames Lab, told Bakac and 

Pestovsky what iron(IV) looks like and what it does. “For 

the first time we knew what both iron(IV) and OH radicals 

would do and could figure out which one is involved in the 

Fenton reaction,” says Bakac. “Nobody knew how to make 

iron(IV) or look at it before so that we could distinguish 

between the two.”

Identical experiments, different products

At that point, knowing the nature of the intermediate, Bakac and Pestovsky decided to carry out some very 

specific experiments. In one set of experiments, they 

oxidized a substance with iron(IV), and in a parallel series 

of experiments, they oxidized the same substance using 

the Fenton reaction.

“The products were different,” says Bakac. “And more 

than that, the products generated from the Fenton reaction 

were identical to those known to be formed from reactions 

involving OH radicals. So we both ruled out iron(IV) as the 

intermediate and indirectly confirmed OH radicals,” she says.

Bakac and Pestovsky’s work took about a year, and not 

every sample was good. “There were times when we 

thought our samples weren’t surviving the trip, so on one 

occasion Oleg actually traveled to Pittsburgh with all of our 

equipment to make the sample there,” recalls Bakac. “It’s 

been rocky at times, but we knew we had something special, and that kept us going.”

In addition to ruling out iron(IV) and indirectly establishing OH radicals as the Fenton intermediate, Bakac and 

Pestovsky’s research shows iron(IV) to be a very useful 

chemical species. “The fact that iron(IV) is very short-lived 

doesn’t matter because in catalytic reactions you make 

it in situ and use it immediately,” says Bakac. “There are 

certainly situations in chemistry and biology where various 

iron(IV) complexes, including our aqueous iron(IV), may be 

involved,” she suggests, then adds; “just don’t go searching 

for iron(IV) anymore in Fenton chemistry.”

For more information:

Andreja Bakac, (515) 294-3544

bakac@ameslab.gov

Research funded by:

DOE Office of Basic Energy Sciences,

 Chemical Sciences Division

Q
18 INQUIRY 2006

USLAN PROZOROV 

adjusts the image on his 

computer monitor, and 

a magnificent geometry 

appears. He’s literally 

seeing the magnetic fields associated with the magnetic moments in 

the crystalline surface of the material under investigation. Somewhat 

reminiscent of fractals – objects that 

display self-similar structure over an 

extended scale range – the geometries Prozorov sees are complex 

and detailed. The intricate patterns 

fascinate him, not only for their 

beauty, but more importantly for 

their potential to reveal more about a 

material’s physical properties.

“One of my deep interests in physics is to relate the geometry of the 

magnetic field patterns to the physical 

properties of a material,” says Prozorov 

an Ames Laboratory associate scientist 

and an Iowa State University assistant 

professor of physics. “There are a 

wide variety of patterns, and I want to 

understand their connection to actual, 

measured physical properties.”

Prozorov says textbooks often 

ignore the intricacy of the magnetic 

field patterns. “Nature behaves in 

a much more complex way than 

textbooks tend to describe,” he 

emphasizes. And for Prozorov, that 

complexity is best studied at the extremely low temperatures associated 

with liquid helium – around 4.2 Kelvin, or minus 452.11 degrees Fahrenheit – just a few degrees above 

absolute zero. At these extremely 

cold temperatures, materials are 

almost completely free of excitations 

and vibrations, making it possible to 

create magnetically ordered or superconducting states – the subjects of 

Prozorov’s investigations.

Magneto-optics “magic”

To shed light on the physical 

properties of a material, Prozorov 

employs magneto-optics, a tool that 

allows him to study the effects arising from the interaction of light with 

magnetized media. By applying his 

own unique experimental techniques, he makes the most of what 

Cunning Patterns of Excelling Nature

Shakespeare’s Othello

From temperatures hovering 

near absolute zero comes 

clever, spectacular physicsR

The tunnel diode resonator allows experimental sensitivity far exceeding commercial 

setups for studying the properties of superconducting materials.

Different magnifications of a neodymium-iron-boron single crystal (grown in senior physicist 

Paul Canfield’s lab) show the distribution of magnetic domains. The elaborate patterns provide 

Ruslan Prozorov with clues to the material’s physical properties. 

Ruslan Prozorov

BY SAREN JOHNSTON
INQUIRY 2006 19 

is a self-resonating circuit that is 

extremely stable and provides experimental sensitivity exceeding commercial setups by orders of magnitude. 

Prozorov uses it to study properties 

of superconducting materials. 

“There are only a few similar 

systems in the United States and 

Europe, and that’s it,” says Prozorov. 

“Cool” work brings recognition

Prozorov’s exceptional work on 

magnetism and superconductivity 

at low temperatures has not gone 

unnoticed. He was selected as one 

of only 23 scientists in the United 

States to receive a 2006 Sloan 

Research Fellowship in physics. The 

prestigious awards are intended to 

enhance the careers of bright young 

faculty members in specified fields of 

science. In addition to the prominence it affords the recipients, the 

Sloan Research Fellowship provides 

a cash reward. Prozorov will receive 

$45,000 over a two-year period, 

which he may use to support any activity directly related to his research.

As he considers how he wants to 

apply the funds he’ll receive from the 

Sloan Research Fellowship, Prozorov 

says he feels fortunate to be a member of the Ames Laboratory research 

community. “Ames Lab is a unique 

place in terms of magnetic and 

superconducting materials, and that’s 

a key ingredient for me,” he says. “I 

don’t generally make materials, but 

I know how to measure them,” he 

adds with aplomb.

 

magneto-optics has to offer. 

“One of the key ingredients is 

that I’m able to reach a wide range 

of temperatures. I can pass liquid 

helium through the system and 

observe a material at a few degrees 

above absolute zero,” he says. 

Taking advantage of the magnetooptical Faraday and Kerr effects, 

which account for the rotation of the 

plane of polarization in a magnetic 

field, Prozorov can observe how the 

magnetic field patterns form and 

explore the connection between 

those patterns and the material’s 

physical properties. “I can literally 

see the magnetic field with my own 

eyes,” he says.

Prozorov explains that magnetism 

comes from electrons and their 

interactions, and each electron has 

a magnetic moment associated 

with it called spin. “Spin is actually 

a mechanical concept, but it’s used 

to refer to the magnetic moment of 

an electron,” he says. In magnetic 

materials, the magnetic moments 

can be aligned either up (spin up) or 

down (spin down). “That’s exactly 

what we’re seeing with the magnetooptics,” he continues. “Spin up corresponds to bright intensities in the 

patterns, and spin down corresponds 

to darker intensities.” He notes that 

these regions of “ups” and “downs” 

might seem fairly basic, but the reality is much more complex, involving 

structures of different length scales 

that are quite fractal in a sense.

Describing his research on magnetism at low temperatures, Prozorov 

says it is both fundamental and applied. He notes that the fundamental aspect revolves around the use of 

new tools, such as his magneto-optical setup, to study and measure the 

physical properties of materials. It’s 

also applied research because unless 

you know how a material behaves 

on a small scale, you don’t know if 

it will behave the way you expect it 

to in a real application. “Part of the 

reason for a material’s unexpected 

behavior may be these complex 

patterns, which, if you understand 

them, may allow you to apply them 

to different things,” he explains.

Low-temp lab

The magneto-optics system combined with the unique experimental 

techniques Prozorov brings to it is a 

mainstay of the new low-temperature lab that he has established in 

one short year since coming to Ames 

Laboratory from the University of 

South Carolina. But it is not the only 

one. A state-of-the-art dilution refrigerator capable of reaching temperatures as low as seven thousandths of 

a Kelvin above absolute zero provides an unimaginably cold environment in which Prozorov can apply his 

innovative methods to study various 

materials and discover more about 

their physical properties.

Perhaps one of Prozorov’s most 

outstanding contributions to the burgeoning low-temperature lab is the 

tunnel diode resonator. The device, 

which is not available commercially, 

For more information:

Ruslan Prozorov, (515) 294-9901

prozorov@ameslab.gov

Research funded by:

DOE Office of Basic Energy Sciences, 

 Materials Science and 

 Engineering Division

National Science Foundation

Alfred P. Sloan Foundation

Ruslan Prozorov prepares a sample for low-temperature magneto-optics study. He applies his 

own unique measurement techniques to analyze 

the relationship between the patterns created in 

the presence of a magnetic field and the macroscopic magnetic properties of the material.

Q
20 INQUIRY 2006

Metamaterials put a new slant on light – 

it’s direction and speed

possible to refract light at a negative angle, so it emerges 

on the left side of the incident beam. This backwardbending characteristic of metamaterials allows enhanced 

resolution in optical lenses, which could potentially lead to 

the development of a flat superlens with the power to see 

inside a human cell and diagnose disease in a baby still in 

the womb.

Whittling down the wavelength

The challenge that Soukoulis and other scientists who 

work with metamaterials face is to fabricate them so that 

they refract light negatively at ever smaller wavelengths, 

with the ultimate goal of making a metamaterial that refracts light at visible wavelengths and achieving the muchsought-after superlens. Admittedly, that goal is a ways off. 

To date, existing metamaterials operate in the microwave 

or far infrared regions of the electromagnetic spectrum. 

The near infrared region of the spectrum still lies between 

the microwave and visible regions, and the wavelengths 

become ever shorter moving along the electromagnetic 

spectrum to visible light. Correspondingly, to negatively 

refract light at these shorter wavelengths requires fabricating metamaterials at extremely small length scales – a 

tricky feat.

However, recent research by Soukoulis and his co-workers from the University of Karlsruhe, Germany, published 

in the May 12, 2006, issue of Science demonstrates they 

have done just that. “We have fabricated for the first time 

a metamaterial that has a negative index of refraction at 

1.5 micrometers,” says Soukoulis. “This is the smallest 

wavelength obtained so far.” Small, indeed; these wavelengths are microscopic and can be used in telecommunications. Soukoulis’ success moves metamaterials into 

FastBackwardMotion

Negatively refracted light. 

BY SAREN JOHNSTON

IGHT FLIES. IT ZIPS BY, MOVING EVER FORWARD

at a mind-boggling 186,000 miles per second, the 

speed at which electromagnetic waves can move 

in a vacuum. That, folks, is “flying!” And Ames 

Laboratory senior physicist Costas Soukoulis and 

his research team are getting in on the action. 

They’re having the times of their lives reversing light’s 

“flight pattern,” making it travel backward at negative 

speeds that appear faster than the speed of light. The 

whole process is what Soukoulis, who is also an Iowa State 

University Distinguished Professor of physics and astronomy, says is “like rewriting electromagnetism.” He predicts, 

“Snell’s law on the refraction of light is going to be different; 

a number of other laws will be different.”

Marvelous metamaterials

There’s no stopping light as it zips along on the fast track 

to anywhere and everywhere it pleases. However, there is 

control. Researchers can manipulate light by using exotic, 

artificially created materials. Known as metamaterials, 

these substances can be created to respond to electromagnetic waves in ways that natural materials cannot. Natural 

materials refract light, or electromagnetic radiation, to the 

right of the incident beam at different angles and speeds. 

(An incident beam is one that strikes a surface.) However, 

metamaterials, also called left-handed materials, make it 

Costas Soukoulis

L

Thomas Koschny
INQUIRY 2006 21

Q

1.5 micrometers with dispersion, we can tune our lasers to 

play a lot of games with light,” says Soukoulis. “This is due 

to the dispersion of the negative index of refraction; there is 

nothing wrong with Einstein’s theory of relativity.”

Making movies 

The detailed interactions of electromagnetic radiation 

within metamaterials lead to phenomena that are counterintuitive and difficult to explain in ordinary terms. To help 

clarify the out-of-the-ordinary nature of the experimental results obtained by Soukoulis and his University of Karlsruhe 

collaborators, postdoctoral fellow Thomas Koschny has 

taken on the additional role of metamaterial movie-maker 

for the research team. He has developed simulations that 

depict a pulse of light entering both a fictitious metamaterial without dispersion and a realistic metamaterial with 

dispersion. So if like most of us you find the relationship 

between electromagnetism and metamaterials a difficult 

one to understand, grab your popcorn and soda and go 

check out the movies at: www.external.ameslab.gov/final/

News/Lightmovies.htm.

For more information:

Costas Soukoulis, (515) 294-2816

soukoulis@ameslab.gov

Research funded by:

DOE Office of Basic Energy Sciences,

 Materials Science and Engineering Division 

Fig. 1: Realistic metamaterial with dispersion – A wave packet 

strikes a physical, dispersive metamaterial slab from the left 

and then travels to the second interface of the slab. The 

group velocity (that of the wave packet) is positive both inside 

and outside the slab. The phase velocity (that of the individual 

wavelengths) is negative inside the slab. There is no violation 

of Einstein’s theory of relativity. The dashed line represents the 

predicted position of the wave packet if the metamaterial slab 

had not been there. 

Fig. 2: Fictitious (theoretical) metamaterial without dispersion — The same situation as in Fig. 1 is shown for an unphysical, dispersionless metamaterial. A wave packet strikes the first 

interface of a nondispersive metamaterial slab from the left. 

While the wave packet is still outside the slab, a response is 

already forming at the second interface of the metamaterial. A 

wave packet is generated and leaves the slab to the right while 

a second packet is sent backwards through the slab (with negative phase and group velocities) and will eventually annihilate 

the original wave packet at the first interface of the slab. This 

situation violates special relativity. Thus, the assumption of no 

dispersion in metamaterials is fictitious (unphysical). 

the near infrared region of the electromagnetic spectrum 

– very close to visible light, which would permit superior 

resolution and a wealth of potential applications. 

Revealing experiments

Not only did Soukoulis and his University of Karlsruhe 

colleagues bring metamaterials closer to visible light, the 

work yielded something unexpected. The researchers 

transmitted a laser pulse through a fictitious (theoretical), 

nondispersive metamaterial (one that does not spread out 

the light pulse into individual wave components with different velocities). The experiment showed that the velocity 

of the individual wavelengths, called phase velocity, was 

negative inside the metamaterial. In addition, the experiment showed, contrary to popular thought, that the velocity 

of the wave packets, called group velocity, can also be 

negative simultaneously.

“We can have a wave packet hit a slab of negative 

index material, appear on the right-hand side of the material and begin to flow backward before the original pulse 

enters the negative index medium,” says Soukoulis. “This 

is possible because the components of the wave packet 

can be reshaped and make a pulse inside the dispersion 

medium before the original pulse enters the negative 

index medium. In this way, one can argue that the wave 

packet travels backward with velocities much higher than 

the velocities of light, seemingly defying Einstein’s theory of 

relativity,” he says. 

In experiments with a more realistic metamaterial with 

dispersion, the researchers found that the phase velocity 

can be either positive or negative, depending on the frequencies of the dispersed light being studied. “When we 

have a metamaterial with a negative index of refraction at 

v

phase

v

group

v

group

v

phase
22 INQUIRY 2006

ESEARCHERS AT AMES

Laboratory can now see 

the atomic structure of materials with unprecedented 

clarity thanks to a new 

$1.8 million scanning transmission 

electron microscope. The new FEITecnai G2 – F20 STEM was installed 

in Wilhelm Hall this summer.

A transmission electron microscope 

uses high-voltage electron beams to 

acquire ultrahigh resolution sample 

images down to Ångström levels for 

analyzing the atomic structure, crystallographic structure and composition 

of specimens. The specimens are 

typically thinned through ion milling or 

other techniques to a film only a few 

nanometers thick so that the beam 

can pass through the sample.

The entire electron path, from gun 

to screen, must be under vacuum 

(otherwise the electrons would 

collide with air molecules and be 

absorbed), so the final image has 

to be viewed through a window in 

New Window on the Nano World

New $1.8 million 

scanning transmission 

electron microscope

the projection chamber. Unlike a 

light microscope with glass lenses, 

the electron beam is focused using 

electromagnetic lenses. By varying 

the current through the lens coil, the 

focal length, which determines the 

magnification, can be varied. 

The scanning function employs 

electron optics to focus the beam into 

a narrow spot. The beam is scanned 

back and forth over the sample to 

form an image.

According to Ames Lab scientist 

Matt Kramer, who is overseeing the 

operation of the STEM, the new scope 

will provide much more than just 

higher resolution than the existing 

Phillips CM30 STEM.

“One of the big differences is in 

the scanning probe size,” Kramer says. 

“While the CM30 in theory could do 

a 1.2 nanometer probe, it had no 

brightness at that fine probe size. The 

new STEM has a probe of 0.18 nm 

with more than a factor of 100 times 

more brightness.” This will allow for 

very precise measurements of chemical changes over a few nanometers.

The new machine also has 

computerized alignment and focusing, which dramatically reduce set-up 

time. Individual users can even save 

specific settings and call them up at 

a later date if they want to look at additional samples.

“The old equipment often required 

hours to align and focus the beam — it 

was really an art,” Kramer says. “The 

new equipment is automated so each 

user can save specific settings, and 

the computer will realign the beam to 

those settings in a matter of seconds.”

Another big difference is the image 

capture. The older machine uses 

photographic plates to record images, 

while the new microscope captures 

digital images that can be displayed 

immediately.

While the new machine can 

perform standard operations, such 

as bright field, dark field and lattice imaging, it also has features 

that allow energy-filtered imaging, 

low-dose imaging, Lorentz imaging, holographic imaging, Z-contrast 

imaging and 3-D imaging. 

“The low-dose imaging is useful 

when working with sensitive materials, 

such as polymer films, that could be 

damaged by the beam,” Kramer says. 

“You can focus the beam on areas 

outside the main area of interest, 

then quickly move to the region you 

want to look at. The older equipment 

doesn’t allow this. By the time you get 

it focused, the beam has disrupted the 

structure of the sample.” 

The Lorentz lenses, coupled with 

the holographic feature, allows vivid 

depiction of features such as magnetic 

fields. And a tomography stage allows 

the sample to be rotated through various views, which are then assembled 

into a 3-D image.

With all these capabilities, the 

equipment is understandably complicated, so not just anyone will have 

access to it. This means long-term 

collaborative projects will be given 

preference along with projects funded 

by the Office of Basic Energy Sciences. BES provided the funding for 

the equipment through a special grant 

in 2005.

Q

R

BY KERRY GIBSON

Viewing polymer films (left) and magnetic fields in materials are just two capabilities now available with the new FEI-Tecnai G2 - F20 scanning transmission electron 

microscope recently installed in Ames Laboratory’s Wilhelm Hall. The $1.8 million 

microscope not only offers high resolution, but takes researchers only a fraction of 

the time to focus and capture digital images. 
Materials Chemistry and 

Biomolecular Materials

John D. Corbett

• F.H. Spedding Award 

 in Rare Earth Research

INQUIRY 2006 23

2005-2006 AWARDS Applied Mathematics and Computational Sciences

Mark Gordon

• ISU Award for Research or 

 Artistic Creativity

• ISU Master Teacher 

 Award

Brett Bode

• IBM Faculty Award. 

 “Management and 

 Control Software for 

 Peta-Scale Systems”

Chemical and Biological Sciences

Mark Gordon

• ISU Frances M. Craig 

Chair Professorship

Edward S. Yeung

• Martin J. Golay Medal

• Merit Award, Chicago 

 Chromatography 

 Discussion Group

Condensed Matter Physics

Ruslan Prozorov

• Sloan Research 

 Fellowship

Costas Soukoulis

• DesCartes Prize 

 (see page 9)

• ISU Distinguished 

 Professor

Surya K. Mallapragada

• Fellow, American Institute 

 of Medical and Biological 

 Engineering

Dan Schectman

• Honorary member,

 Japan Institute of Metals

Mufit Akinc

• Ross Coffin Purdy Award, 

 American Ceramic Society

Cynthia Jenks

• ISU Professional and 

Scientific CYtation Award

• Board of Regents Staff 

 Excellence Award

Brian Gleeson

• ISU Alan and Julie Renken 

 Professor in Materials Science 

 and Engineering

Vitalij K. Pecharsky

• ISU Anson Marston 

Distinguished Professor 

of Engineering

Karl A. Gschneidner, Jr.

• ISU Materials Science 

 and Engineering Excellence 

 in Research Award

Materials and Engineering Physics

Paul Canfield

• ISU Distinguished

 Professor

Patricia A. Thiel

• Dr. Honoris Causa, 

 Institut National 

 Polytechnic de Lorraine
24 INQUIRY 2006

Ames Laboratory’s education 

programs this year spanned the range 

from elementary school students to 

undergraduates, through tours and 

science night activities, Middle School 

and High School Regional Science 

Bowls and the Science Undergraduate Laboratory Internship program. 

And steps are underway to extend 

that even further, bringing middle teachers into 

the laboratory setting 

for an intensive science 

education experience.

For the16th straight 

year, teams of high 

school students from 

across Iowa traveled to 

Ames the last weekend 

in January to participate 

in the Ames Laboratory/ISU Regional 

High School Science Bowl. After 

losing an early match to defending 

champion Ames High School, Iowa 

City Regina advanced to the finals and 

defeated Ames twice to win the 2006 

championship and advance to the 

National Science Bowl.

At the national competition, the Regina team of Phil Shiu, Peter Montag, 

EDUCATION

Josh Hove and Stephen Berg made a 

strong showing, placing in the “Sweet 

16” teams and winning $1,000 for 

the school.

 “I’m so proud of these students,” 

said Regina coach Barb Reilly. “It’s 

amazing that a school our size (less 

than 300 high school students) was 

able to get to this level.” In comparison, Miami Palmetto High School, 

which eliminated Regina from competition, had 3,400 students. Reilly 

said the Regina team will consider 

using their winnings to purchase a 

mini library of information and review 

items that will help future teams 

prepare for Science Bowl, 

or they may outfit a lab or 

buy a microscope.

Evans Middle School of 

Ottumwa, winner of the 

Ames Lab/ISU Regional, 

also finished in the money 

at the 2006 National Middle 

School Science Bowl, held June 

21-24 in Denver, Colo. The Evans 

team of Estefany Garcia, Andrew 

Kaake, Samantha Robertson, Jake 

Swanson and Jacqueline Vonderhaar 

finished fourth in the 25-team middle 

(above) A team of middle schoolers assembles 

a hydrogen fuel-cell car during the opening day 

of competition.

(below) High school students from 

Clay Central-Everly confer on a 

bonus question during the Ames 

Lab/ISU High School Science 

Bowl competition. 

 

school competition, 

winning $500 for their 

school. Evans advanced 

to the national competition 

by defeating Boone Middle School 

in the Ames Laboratory/ISU regional 

championship on April 8.
Teaching teachers

In addition to undergraduate students, Ames Lab will begin a program 

to bring middle school teachers into 

the laboratory setting for an intensive 

science-education experience. Called 

Laboratory Science Teacher Professional Development, or LSTPD, the 

program will bring10 teachers from 

middle schools from Iowa, Minnesota 

and South Dakota to Ames Lab and 

ISU to participate in the Teachers as 

Investigators program. Through the 

program, teachers will learn how to 

bring exciting breakthroughs and frontiers of science into their classrooms, 

while conducting hands-on, discoverybased experiments with advanced 

equipment.

 In coordinating the LSTPD 

program, Ames Laboratory joins a 

nationwide effort on the part of DOE’s 

national laboratories in inspiring, 

educating and encouraging a new 

generation of scientists who will be 

equipped to “enhance the science 

literacy of the nation.” This initiative is 

in keeping with the recommendations 

of the Secretary of Energy Advisory 

Board’s Science and Mathematics 

Education Task Force, which recognize 

the role teachers, especially middle 

school teachers, play in “maintaining 

students’ enthusiasm for science.” 

The proposed program will require a 

four-week commitment from teachers 

each summer for three years.

Year two for SULI

A new group of 10 aspiring scientists participated in the second year 

of Ames Lab’s Science Undergraduate Laboratory Internship or SULI, 

program. Funded by the Department 

of Energy’s Office of Science, the 

program focuses on providing internships in real-world research settings at 

DOE national laboratories to students 

interested in careers in science and 

engineering.

Year two of SULI had students 

working with their Ames Lab/ISU 

mentors for a10-week period – two 

weeks longer than the 2005 inaugural 

program — to give participants more 

time to complete research projects 

and write papers. This year’s program 

began May 30 and continued through 

August 4.

 One of DOE’s objectives for the 

SULI program is to encourage participation by students whose home 

institutions do not have major research facilities. To help achieve that 

objective, DOE asks its national labs 

to make the internships available to 

students who aren’t attending universities in their own backyards. This year’s 

SULI students were all from out of 

state. Universities and colleges represented included Pennsylvania State 

University; Western Illinois University; 

Moraine Valley Community College (Illinois); Ohio State University; Michigan 

Technological University; BYU, Idaho; 

Westminster College (Missouri); University of Kansas, Lawrence; Colorado 

School of Mines; and Carnegie Mellon 

University (Pennsylvania).

(above) SULI student DeAnna Jones, BYU, Idaho, performs research on the 

synthesis of magnetic nanoparticles. She worked with mentor Surya Mallapragada and research associate Tanya Prozorov.

(below) Ryan Glamm, SULI student from Ohio State University, studies 

the crystallography of fractured metal surfaces. He worked with mentors 

Barbara and Tom Lograsso. 

INQUIRY 2006 25
Ames Laboratory

111 Technical and Administrative Services Facility

Ames, Iowa 50011-3020

515-294-9557

www.ameslab.gov

A U.S. Department of Energy laboratory operated by Iowa State University