bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gold Nanoparticles: Monolayer‐Protected Scaffolds and Building Blocks
Authors: Ofir Yuval , Srivastava Sudhanshu , Rotello Vincent M. 
Published: December 2011

Abstract
Nanoparticles provide key tools for bridging the gap between “bottom‐up” synthetic methods and “top‐down” fabrication. In this article, we describe recent progress in the recognition‐mediated assembly of metal nanoparticles using small molecules and polymers. A significant portion of the article focuses on the interaction of nanoparticles with biological moieties such as peptides and proteins, and the use of nanoparticles as drug and gene carriers for application in biomedical applications.
Inorganic Nanobelt Materials
Authors: Yu Shu‐Hong , Yao Wei‐Tang 
Published: December 2011

AbstractThe aim of this article is to provide a comprehensive review of current research activities that center around inorganic nanobelts. We begin with an overview of synthetic strategies and principles that have been developed for generating 1‐D nanobelts with vapor‐phase growth as well as solution‐based growth routes. We then discuss the synthesis and structure of various inorganic nanobelts, which include elements, oxides, hydroxyl sulfates, chalcogenides, arsenides, phosphides, nitrides, carbon, and carbides. Toward the end, we highlight a range of innovative applications enabled by the unique combination of different potential properties of inorganic nanobelts. Continued development of the synthesis strategies and the preparation procedures as well as functionalization of nanobelts for novel applications will provide significant breakthroughs.
Metal Oxide Nanoparticles
Authors: Fernández‐García Marcos , Rodriguez José A. 
Published: December 2011

AbstractThis article covers the fundamental science, synthesis, characterization, physicochemical properties, and applications of oxide nanomaterials. It also explains the fundamental aspects that determine the growth and behavior of these systems, briefly examines synthetic procedures using bottom‐up and top‐down fabrication technologies, discusses the sophisticated experimental techniques and state‐of‐the‐art theory results used to characterize the physicochemical properties of oxide solids, and describes the current knowledge concerning key oxide materials with important technological applications.
Nanoporous Metal Phosphonates
Authors: Miller Stuart R. , Wright Paul A. 
Published: December 2011

Abstract

Nanoporous metal phosphonates make up a growing family of organic–inorganic hybrid solids, which extends the scope of functional materials with potential in adsorption, ion exchange, catalysis, and sensing. Their attributes include thermal stability and the ability to incorporate functional organic and inorganic components accessible to adsorbates. The best established are those based on zirconium, comprising layered solids in which organic groups act as pillars between inorganic zirconium phosphate sheets. The porosity, which can be on the micro‐ or mesoscale, is engineered by design of the organic pillars and their number density and, while not ordered on the long range, can have a narrow distribution. Other pillared layered metal phosphonates are also known. More recent developments have yielded framework metal phosphonates with well‐defined permanent microporosity similar to that observed in zeolites, in the 0.3–1‐nm range, that demonstrate molecular sieving. Currently, the most promising solids of this kind include aluminum methylphosphonates and metal bisphosphonates, which can be described as
metal–organic frameworks
or MOFs. Another area of smaller, but developing interest is the preparation of metal phosphonates with ordered mesoporosity, in which a wide range of solids with relatively narrow distribution of pore sizes in the 3–15‐nm range is prepared by surfactant‐templated approaches. These have potential in the interaction with large molecules, including proteins.
Nano/Microporous Materials: Nanostructured Layered Double Hydroxides
Authors: Leroux Fabrice , Prévot Vanessa 
Published: December 2011

AbstractThis review summarizes developments in nanostructured layered double hydroxide (LDH) materials for the period 2004–2007. Particular attention is paid to synthesis aspects, including coprecipitation, urea decomposition, sol‐gel processing and derivative methods as well as the generation of functional materials through delamination either from solvent solution or in situ within a polymer. Coating processes, illustrated by the heterogeneous growth of nanorods onto LDH surfaces, is distinguished from particle nanostructuration. In addition, nanostructuration from LDH frameworks is described for iron‐based oxides and other metal oxides in which catalytic, magnetic, or energy‐storage properties are discussed. Other examples of nanostructuration, such as complex encapsulation, are demonstrated not only with different complexes, such as polyoxometallates and porphyrines but also with rare earth and quantum dot materials, where interest is focused on luminescent and optical properties. Additionally, drug encapsulation and/or release, gene‐reservoir applications, and incorporation of DNA and bioinorganic enzymes into LDH assemblies nicely illustrate biologically related uses of LDH nanoplatelets. Finally, reactions occurring within LDH interlayer spaces are described, and the role of LDH framework as a nanoreactor is illustrated by in situ polymerization of conjugated polymers and thermoplastics. LDH materials can also be used as sacrificial templates for fabricating nanosized polymers and for the synthesis of carbon replica and carbon fibers.
Nanocomposite Materials: Semiconductors in Zeolites
Authors: Goldbach Andreas , Saboungi Marie‐Louise 
Published: December 2011

Abstract
Encapsulation in zeolites holds considerable promise for organizing semiconductor quantum dots and quantum wires into ordered two‐ and three‐dimensional arrays that can be used in a variety of applications. While the use of such materials has been limited until now by a number of practical difficulties, considerable progress has been made in the last few years in surmounting these obstacles. This article reviews recent progress in the field, particularly with regard to stabilization of the nanocomposites against moisture, modulation of their properties by appropriate cation substitution, and preparation of materials in the form of thin films that can exhibit strong nonlinear optical activity. Finally, the article discusses the present perspectives for the field and outlines some research directions that must be pursued for these materials to achieve their full range of potential applications.
Molecular and Supramolecular Arrays of the [
Re
6
(μ
3
‐
Se
)
8
]
2+
Core‐Containing Clusters
Authors: Zheng Zhiping 
Published: December 2011

Abstract

Transition metal clusters are a unique class of chemical substances. Not only do they have well‐defined molecular structures, they also exhibit interesting and potentially useful properties that are inherent to metal–metal bonded species. In this contribution, our efforts in developing synthetic methodologies necessary to bring a cluster system out of the limited sphere of fundamental cluster chemistry and into general synthetic applicability are summarized. Specifically, we have explored the uses of site‐differentiated cluster complexes of the [Re
6
(μ
3
‐Se)
8
]
2+
core as stereospecific building blocks for supramolecular construction. A great variety of cluster‐supported molecular and supramolecular architectures have been realized. These include Tinkertoy‐like molecular cluster arrays featuring cluster units bridged by multitopic ligands and supramolecular assemblies of clusters engineered via hydrogen bonding and metal–ligand coordination. Some of these nanoscopic cluster‐containing systems display rather interesting electronic and spectroscopic properties and, therefore, hold great potential in developing molecule‐based electronic and optical materials. The work therefore marks the beginning of what promises to be an exciting new chapter in cluster chemistry.
Nanostructured Catalysts: Controlling Single‐Site Composition
Authors: Barnes Craig E. , Mayes Richard T. 
Published: December 2011

Abstract
Developing well‐understood methodologies for the preparation of single‐site catalysts has long been a goal in catalysis science. Newly emerging strategies for preparing and functionalizing nanostructured materials open the door to a number of new approaches that address this goal. General, structural, and chemical definitions of nanostructured, single‐site catalysts are presented, and the challenges associated with meeting these requirements are discussed. Selected examples of nanostructuring strategies that lead to well‐defined single‐site catalysts are described.
Endohedral Fullerenes
Authors: Yang Shangfeng , Dunsch Lothar 
Published: December 2011

AbstractThe recent state in endohedral fullerenes is reviewed in terms of both sides of the fullerene: the new carbon cages including non‐IPR (IPR, isolated pentagon rule) structures as well as new species encaged in the inner fullerene void. A general principle is valid nowadays and used in endohedral fullerene research: the stabilizing ability of the encaged structure for the fullerene cage architecture and that of the fullerene cage for the encaged species. Thus, the cage size ranges from C66, the first non‐IPR fullerene cage, to C100while the encaged species are extended up to five atomic clusters as for Sc3C2. The world of endohedral fullerenes was significantly enlarged within the past seven years by the cluster fullerenes containing structures like the M3N nitrides. This review is focused on the new development of this amazing world of carbon nanostructures since 1999, including new structures, properties, and potential applications of endohedral fullerenes as well as prospects.
Inorganic Nanomaterials Synthesis Using Liquid Crystals
Authors: Boissière Cédric , Grosso David , Prouzet Eric 
Published: December 2011

Abstract
Soft matter offers a unique property that combines high order with specific geometry and high dynamics that allows this geometry to adapt easily to rapid changes in physicochemical parameters. This property has been used in many systems for the formation of nanostructures when a soft matter such as liquid crystals acts as a mold that can be easily tuned and also removed once the material has been synthesized. In this review, we describe the general bases of the mechanisms that lead to nanostructured materials. Specific emphasis is given on the evaporation‐induced self‐assembly (EISA) method, where a liquid crystal is obtained upon drying of a complex solution during evaporation in a thin film. We also describe how surface micropatterning can be obtained by coupling solid‐state chemistry and soft matter and perspectives based on versatility of liquid crystals.
Biomimetic Chemistry of Hybrid Materials
Authors: Rurack Knut , Martínez‐Máñez Ramón 
Published: December 2011

AbstractThe article discusses representative examples published in the field of functional biomimetic chemistry of hybrid materials between 2004 and mid‐2007. First, we focus on the modification of morphological aspects of (bio)organic–inorganic hybrid materials to create sophisticated gating and switching mechanisms. The architecture of the systems is presented and the elements of control by external stimuli that have been established in recent years, such as optical, electrochemical, chemical, thermal, or magnetic means, are described. Various functions ranging from (site‐specific) delivery to indication at the nanometric level are reported. Next we develop the idea of utilizing hybrid frameworks for biomimetic signaling inspired by the way nature has created binding pockets and the concept of induced‐fit. Such a merging of inorganic scaffolds with supramolecular concepts results in enhanced molecular recognition and signaling. Finally selected recent advances in the field of hybrid biomimetic motors both of linear and rotary types are presented. The contribution shows how novel biomimetic functions can arise from synergisms between specifically designed hybrid materials and the implementation of supramolecular and/or bioorganic concepts.
N‐Heterocyclic Carbene‐Containing Metal Complexes
Authors: Fantasia Serena , Clavier Hervé , Nolan Steven P. 
Published: December 2011

AbstractIn the last decade, coordination chemistry has witnessed the advent of a new class of ligands: theN‐heterocyclic carbenes (NHCs). The “success story” associated with this ligand family can be explained by the unique stereoelectronic properties of the NHCs; these unique properties have led to their numerous applications in catalysis. This article provides an overview of developments and recent advances in the syntheses of NHCs and NHCtransition metal complexes. For these NHC ligand‐containing complexes, an analysis focuses on stability and reactivity patterns is provided. Reactions such as the cleavage of NHCmetal bond, CH and CC activations, NHC migration, and NHC insertion are presented.
Medicinal Inorganic Chemistry: Continuum of Dose versus Response—From Deficiency through Optimal Intake to Toxicity
Authors: Thompson Katherine H. 
Published: December 2011

AbstractMetal‐ion essentiality is not a static concept. Over the course of the last several decades, essentiality has been redefined to broaden the definition beyond “necessary to support human life” to include “having a defined biochemical function.” The main effect of this redefinition has been to restrain the addition of additional ultratrace elements, present in the human body, but not clearly required in a specific amount in the daily nutrient intake, to the ever‐expanding list of known essential elements. Essential metal ions are associated not only with recognizable deficiency symptoms under conditions of inadequate intake but also with existing homeostatic mechanisms that regulate absorption, distribution, storage, and excretion of the metal‐ion in vivo. The Bertrand diagram is a schematic representation of the range of essential metal‐ion intake consistent with optimal nutrient intake, bounded on the lower intake range by deficiency symptoms and on the upper intake end, by increasingly severe toxicity symptoms. The continuum of dose versus response includes both tails of this spectrum for all essential metal ions. Not all metal ions are the same: each has an appropriate “window of optimal intake” whose width and concentration ranges vary widely from one metal ion to the other.
Medicinal Inorganic Chemistry: Metallotherapeutics for Chronic Diseases
Authors: Thompson Katherine H. 
Published: December 2011

AbstractMetal‐containing therapeutic agents designed for use in chronic disorders, such as gastrointestinal dyspepsia, bipolar disease, diabetes mellitus, osteoporosis, and arthritis, present additional challenges to the medicinal chemist. Beyond the immediate toxicity issues seen with acute disease treatments, chronic use of metallotherapeutic agents may result in metal ion accumulation or in gradually developing intolerance that can require discontinuation of the drug. Metallotherapeutic agents that have passed the rigorous testing required for chronic use include bismuth subsalicylates, for a variety of gastrointestinal disorders; lithium carbonate, for bipolar disease; lanthanum carbonate, for end‐stage renal disease; strontium ranelate, for osteoporosis; and the gold‐based antiarthritic, Auranofin™, although the last has fallen out of favor. Chromium picolinate is an approved nutritional supplement, a designation that allows less stringent testing than for new chronic‐use drugs. Among those compounds not currently approved for clinical use, but showing promise, the copper – indomethacin and zinc – indomethacin complexes, for inflammation resulting from rheumatoid arthritis; vanadium compounds, for glucose‐ and lipid‐lowering in type 2 diabetes mellitus; and selenium compounds, as possible cancer preventatives, are worthy of consideration.
Medicinal Inorganic Chemistry: Sequestration or Removal in Metal Ion Overload Disorders
Authors: Thompson Katherine H. 
Published: December 2011

AbstractAll metal ions, whether essential or nonessential, are toxic when present in excess. Metabolic disorders in which metal ion overload is a key contributing factor include hemochromatosis, β‐thalassemia, Wilson's disease, Menkes syndrome, and Friedreich's ataxia. For some metal ions, overload conditions may come about as a result of excess oral, inhalation, or dermal exposure. In order to correct a metal ion overload condition, an appropriate ligand choice may speed up the elimination or safely sequester the excess metal ion, and may be the treatment of choice. A number of effective chelating agents are discussed, including desferrioxamine, deferiprone,D‐penicillamine, and copper– histidine chelate. Marginal overload conditions may lead to marginal deficiency of another metal ion, a result, paradoxically, from single metal ion supplementation. An example would be marginal iron overload, resulting from iron supplement use in excess of need, which leads to marginal manganese deficiency. Such effects are due to metal ion interaction effectsin vivo.
Spectroscopic Properties Obtained from Time‐Dependent Density Functional Theory (TD‐DFT)
Authors: Autschbach Jochen 
Published: December 2011

AbstractThis article summarizes basic aspects of time‐dependent density functional theory (TD‐DFT) and its applications in inorganic chemistry. Sections titled TD‐DFT and Spectroscopic Properties outline some of the theoretical formalism and explain how excitation energies can be obtained from TD‐DFT linear response theory. Common approximations in density functional theory (DFT) exchange‐correlation (XC) potentials that might have adverse effects on the accuracy of computed results are explained. Sections titled Benchmark Data and Some Case Studies discuss a number of case studies, with emphasis on TD‐DFT excitation spectra computations in coordination chemistry. Computations of spectra and other properties of metals clusters are also discussed. Apart from excitation spectra, this section also describes TD‐DFT computations of Raman intensities (including resonance Raman and surface‐enhanced Raman spectra (SERS)), magnetic circular dichroism, optical rotatory dispersion (CD and ORD), and concludes with some comments on relativistic effects.
Spectroscopic Properties of Protein‐Bound Cofactors: Calculation by Combined Quantum Mechanical/Molecular Mechanical (
QM
/
MM
) Approaches
Authors: Sundararajan Mahesh , Riplinger Christoph , Orio Maylis , Wennmohs Frank , Neese Frank 
Published: December 2011

Abstract

In this article, we discuss some aspects of the combined quantum mechanics/molecular mechanics (QM/MM) method for the calculation of energetics and spectroscopic parameters of protein‐bound cofactors. Following a brief introduction to the theory of the QM/MM approach, some selected examples are discussed that illustrate the use of this methodology in theoretical spectroscopic studies. The examples cover the following: (i) excitation energies for the
S
0
→
S
1
transition in bacteriorhodopsin; (ii) electron paramagnetic resonance (EPR) and absorption spectra of plastocyanin; and (iii) the spin Hamiltonian parameters of compound I in cytochrome
P
450
cam
.
Quantum Mechanical/Molecular Mechanical (
QM
/
MM
) Methods and Applictions in Bioinorganic Chemistry
Authors: Ryde Ulf 
Published: December 2011

Abstract
The combination of quantum mechanics and molecular mechanics (QM/MM) methods is a promising approach to study the structure, function, and properties of proteins. The number of QM/MM applications on metalloproteins has been steadily increasing and it is the method of choice to study the influence of the protein onto the structure, spectroscopy, and energetics of an active site. In particular, it has been shown that QM/MM calculations can provide geometries of metal sites in proteins with an accuracy that is better than in low‐ and medium‐resolution crystal structures. However, it is quite hard to obtain reliable and converged energies. Therefore, QM/MM is still an area of method development and no consensus of the best treatment of a protein has yet been reached. This review covers various aspects of QM/MM studies of metalloproteins, including methods to incorporate experimental data in the calculations, methods to obtain reliable energies, as well as some examples of typical applications.
Computational Studies: Proton/Water Coupling to Metals in Biological Reaction Mechanisms
Authors: Bu Y. , Cukier R. I. 
Published: December 2011

Abstract
Metalloenzymes promote a wide variety of reaction chemistry with the use of protons and water, and associated ligands and protein residues. The charges/oxidation states of the metals and many charged and/or highly polar residues and ligands produce strong effects on acid‐base‐driven chemistry. Computational approaches to metalloenzyme mechanisms require a compromise between accuracy (use of high‐level quantum chemical methods) and the ability to handle many atoms (use of force field methods). Methods that divide the system into a part that is treated accurately and a part treated at a lower level require careful attention toward the chemistry of the specific system. In this article, we outline a number of our recent approaches to some enzymatic reactions where metals, protons, and water are intimately coupled. Three metalloenzymes, cytochrome c oxidase, cytosine deaminase, and calcium ATPase (a calcium pump), are discussed using methods that divide an enzyme into a reaction zone treated at a high level and the remainder treated at a lower level.
Computational Studies:B12Cofactors and their Interaction with Enzyme Active Sites
Authors: Brunold Thomas C. 
Published: December 2011

AbstractCyanocobalamin, commonly known asvitamin B12, and its biologically active derivatives, 5′‐deoxyadenosylcobalamin (AdoCbl) and methylcobalamin (MeCbl), have long fascinated scientists with their elaborate structures and intriguing reactivities in enzymatic systems. While the large size and complex electronic structures of these cofactors have posed a major challenge for theoretical chemists, recent insights gained from kinetic, spectroscopic, and X‐ray crystallographic studies have established an excellent foundation for validating computational investigations of the geometric, electronic, and reactivity properties of the isolated cofactors and the molecular details of the catalytic cycles of B12‐dependent enzymes. This review—which is by no means exhaustive—summarizes salient information that has been obtained from experimentally validated computational studies of the following: (i) the free B12cofactors in their Co3+, Co2+, and Co1+oxidation states; (ii) the mechanism by which enzymes involved in the biosynthesis of AdoCbl overcome the large thermodynamic barrier associated with the Co2+ → Co1+reduction; (iii) plausible strategies by which AdoCbl‐dependent enzymes achieve a trillion‐fold rate of acceleration for thehomolyticcleavage of the cofactor's CoC(Ado) bond; and (iv) the means by which MeCbl‐dependent methyltransferases regenerate the active MeCbl cofactor and accelerate the rate of methyl transfer viaheterolyticCoC(Me) bond cleavage by as many as 6 orders of magnitude.
Electronic Structure Calculations: Transition Metal—
NO
Complexes
Authors: Ghosh Abhik , Hopmann Kathrin H. , Conradie Jeanet 
Published: December 2011

Abstract
The advent of density functional theory led to a major exploration (and, in some cases, a reexploration) of key aspects of transition metal nitrosyls. Many of these developments are reviewed here for the first time, with comparable emphasis placed on both heme/metalloporphyrin and nonheme systems. The latter exhibit diverse electronic structures, which we have described in some depth. Several of the open‐shell species described exhibit broken‐symmetry electronic structures, with significant spatial separation of majority and minority spin densities.