bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phosphorus: Inorganic ChemistryBased in part on the article Phosphorus: Inorganic Chemistry by Josef Novosad which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Kelly Paul F. 
Published: March 2006

Abstract

The element phosphorus was first discovered in 1669, and some measure of the growth of its uses and importance since then is evident from the fact that approximately half a million tons of the element are now produced annually; in addition, phosphorus‐based materials may be generated from naturally occurring phosphates, and for this reason over 130 million tons of such material are utilized per annum. Its importance to life means that natural phosphorus cycles occur; in addition, utilization of the element and its compounds is key to many industrial processes (producing products varying from pesticides to oil additives). In the laboratory, work has shown that many ‘naked’ phosphide anions can be prepared – these can even mimic organic systems, as in the case of the cyclo [P
5
]
−
ligand, which binds face on to metals in the manner of the cylcopentadienyl ligand. In addition, there are many examples of transition metal complexes of ligands containing only phosphorus; these range in size from just a single phosphorus atom to complex structures containing up to 14 atoms. Away from transition metal chemistry, phosphorus forms compounds with elements from all groups of the periodic table barring the noble gases; this article provides an overview of such compounds, with special interest in compounds that have an industrial use, that stabilize unusual bonding arrangements, or that are of current interest. In the process, it highlights the ability of the element to become involved in catenation and to form small cluster units, often with many PP bonds present. Thus, group 13 compounds of the element include the industrially important phosphides and a recently prepared new class of boron–phosphorus polymer. Silicon compounds of the element often exhibit unusual structures and some of these are illustrated and reference is made to multiple‐bonded systems, including the first example of a phosphabismuthene. Sulfides such as P
4
S
10
and halides such as PCl
3
and POCl
3
are of immense industrial importance and details of such processes and the consumption levels are provided. References to recent reviews on a range of pertinent topics are provided, including PSi chemistry, phosphides, phosphorus‐based polymers, phosphorus complexes of transition metals, phosphorus‐borane chemistry, phosphane ligands, organophosphorus chemistry, and phosphorus hydrides.
Phosphorus–Nitrogen CompoundsBased in part on the article Phosphorus–Nitrogen Compounds by Robert H. Neilson which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.
Authors: Haiduc Ionel 
Published: March 2006

AbstractPhosphorus displays several oxidation states (+II,+III, +IV, and+V) and coordination numbers (from one to six), and with nitrogen (also two‐, three‐, and four‐coordinate) can form a broad variety of compounds (purely inorganic or organo‐N‐ or ‐P‐substituted). In addition to mononuclear PN compounds, many short‐chain, polymeric, and cyclic compounds based on molecular skeletons formed by PN alternation are known. There are numerous classes of phosphorus–nitrogen compounds, and this article makes an attempt to introduce the most important ones in the limited space available by selecting what seem to be the most illustrative examples from a very rich chapter of chemistry.
Phosphorus: Organophosphorus Chemistry
Authors: Engel Robert , Cohen JaimeLee Iolani 
Published: March 2006

AbstractThe chemistry associated with compounds bearing at least one carbon–phosphorus bond has been surveyed. This survey has been organized on the basis of the coordination about the phosphorus center, beginning with monocoordinated phosphorus and continuing through hexacoordinated phosphorus. Preparations, stereochemistry, and reactivity are principal topics considered.
Photochemistry of Transition Metal ComplexesBased in part on the article Photochemistry of Transition Metal Complexes by Lisa McElwee‐White which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.
Authors: Bitterwolf Tom 
Published: March 2006

AbstractPhotochemistry has evolved into a powerful tool for the highly selective generation of reactive intermediates in inorganic and organometallic chemistry. This review examines the state of the art in the examination of mechanisms of photochemical reactions utilizing techniques such as frozen matrices and fast time‐resolved methods. The application of photochemistry to the preparation of dihydrogen, alkane, and noble gas intermediates is reviewed along with the significance of these intermediates in the understanding of the mechanism of oxidative addition processes. Experiment and theory of charge transfer phenomena are extensively discussed along with the application of these processes to semiconductor and biochemical studies. Applications of photocrystallography to the examination of linkage isomers and very short‐lived excited state species are reviewed. Finally, a number of examples of the application of photochemical reactions, such as the photolysis of Fisher carbene species to generate ketenelike intermediates, to synthesis are discussed. The literature is reviewed to the end of 2003.
Photochemistry of Transition Metal Complexes: TheoryBased in part on the article Photochemistry of Transition Metal Complexes: Theory by Jeffrey I. Zink which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Daniel Chantal 
Published: March 2006

Abstract
The most significant developments in quantum chemistry and wave packet dynamics that provide the theoretical tools to study the electronic spectroscopy and photoreactivity of transition metal complexes are presented. The difficulties inherent to this class of molecules as well as the degree of maturity of the theoretical approaches are discussed. Recent applications in the chemistry of transition metal complexes are selected to outline and to illustrate the necessity for a strong interplay between theory and experiments.
Photoelectron Spectroscopy of Transition Metal Systems
Authors: Green Jennifer C. 
Published: March 2006

Abstract
Photoelectron spectroscopy measures the binding energies of electrons in molecules and solids. The article briefly considers experimental methods. A photoelectron spectrum is related to the molecular orbital structure of a system. Variation of the band intensities with photon energy gives information on the atomic orbital content of the originating molecular orbital. Band splitting may have a number of origins such as vibrational states, Jahn–Teller distortions, exchange splittings, and spin–orbit coupling. All of these provide additional information on electronic structure. Density functional calculations of ionization energies give good agreement with experiment. All these points are exemplified throughout and the article concludes with a number of case studies.
Photosynthesis
Authors: Staples Christopher R. , Blankenship Robert E. 
Published: March 2006

AbstractPhotosynthesis is a biological process in which light energy is captured and stored as chemical energy by organisms such as plants, algae and certain bacteria. The stored energy is then used to power cellular processes. Most organisms that perform photosynthesis utilize chlorophylls or bacteriochlorophylls, in conjunction with other pigments such as carotenoids, pheophytins, and bilins. The emphasis in this article will be on the aspects of photosynthesis that relate most directly to the subject of inorganic chemistry. The aspects presented include excited states, photochemical reactions, the role of metal ions in photosynthesis, the structures of pigments, electron transfer pathways, reduction potentials of components, chromophore absorption and fluorescence spectra, energetics, and kinetics. Recent crystal structures of photosystems I and II, the important enzyme cytochromeb6f, and antenna complexes and supercomplexes are presented and discussed.
Platinum‐Based Anticancer DrugsBased in part on the article Platinum‐Based Anticancer Drugs by Steven J. Brown, Christine S. Chow & Stephen J. Lippard which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Robillard Marc S. , Reedijk Jan 
Published: March 2006

Abstract
The chemotherapeutic agent cisplatin enjoys the status of one of the world's best‐selling anticancer drugs. As is the case with other chemotherapeutic drugs, however, cisplatin has its drawbacks, including intrinsic or acquired resistance and toxicity. Efforts to mitigate cisplatin's drawbacks have inspired the synthesis of myriad analogs, but with only a handful that have been shown to be acceptable for clinical application. Increased understanding of the mechanism of the action of cisplatin, as a result of decades of research, is leading to a more rational design of new platinum drugs. However, the incomplete puzzle of cisplatin's ways and the lack of a single decisive biological target for anticancer treatment still complicate the search for improved platinum drugs. This article gives a brief introduction to cisplatin, and subsequently summarizes and evaluates the development of cisplatin derivatives and possible new approaches.
Platinum: Inorganic & Coordination Chemistry
Authors: Crabtree Robert H. , Torrens Hugo 
Published: March 2006

Abstract

The article
Platinum: Inorganic & Coordination Chemistry
includes some historical highlights related to this metal as well as some properties and uses of platinum. Its inorganic and coordination chemistry is illustrated briefly through some specific chemical compounds and reactions. Binary compounds with halides, chalcogen, and related ligands are described. Platinum oxidation states 0 to IV are deal with on separated headings: compounds of Pt(0) predominantly with phosphine ligands; complexes of ‘monovalent’ platinum with PtPt bonds; Pt(II) with a large range of ligands; ‘trivalent’ platinum compounds and finally Pt(IV) bound to a variety of donor atoms. Nearly 70 references help the reader to follow specific topics.
Platinum: Organometallic ChemistryBased in part on the article Platinum: Organometallic Chemistry by Charles M. Lukehart which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Chen Jwu‐Ting 
Published: March 2006

Abstract
This article aims to describe the prominent advances of organoplatinum chemistry in the latest decade. Recent development in this field has been much advanced with the design of new ancillary ligands as well as new organic ligands. For the former, the polydentate cyclometallated ligands, tridentate pincer ligands, nitrogen‐donor ligands, and aminocarbenes are discussed. For the latter, in addition to the synthesis and structure of new organoplatinum compounds, a noteworthy growth is to exploit some of these compounds for luminescent materials. The content in this regard is brief since it has been covered as an independent article of this volume. Organoplatinum species with unprecedented bonding modes or new organometallic functionalities are discussed separately. The progress of nano sciences prompts the conceptual revolution in the whole frontier line of chemical research. Organoplatinum chemistry has been contributing in a profound way to construction of the new substances of large skeletons. Exploration starting from clusters and molecular assemblies to organometallic polymers, particularly with rational design, is addressed. Reactions involving the SiH, SiSi, CH, and CC bond formation or cleavage are crucial to hydrosilylation and alkane functionalization respectively. Platinum‐silylene chemistry accounts for a major breakthrough in synthetic chemistry. As to platinum‐hydrides that are mainly concerned in Pt(IV)‐state and are key intermediates in alkane activation, their syntheses and structures are discussed in Section 5. Platinum(IV)‐alkyls are the theme of Section 6. The reaction mechanisms of Pt(II)/Pt(IV) involving aqueous CH activation and other reactions or catalysis involving organoplatinum are summarized at the end.
Polonium: Organometallic Chemistry
Authors: Zingaro Ralph A. 
Published: March 2006

Abstract
The organometallic chemistry of polonium has received limited research effort. The element is very rare, and all of its isotopes are radioactive. Radioactivity causes rupture of the bonds between carbon and polonium. Also, because polonium is a heavy metal, chemical bonding to carbon is thermodynamically very weak. It is rare for an organometallic compound of polonium to be isolated in weighable quantities and characterized using the conventional techniques of organic chemistry. The identification of organopolonium compounds relies largely on chromatographic behavior and on the use of tellurium compounds having analogous chemical structures as reference compounds.
Ruthenium: Organometallic ChemistryBased in part on the article Ruthenium: Organometallic Chemistry by Ulrich Koelle which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: White Rosemary E. , Hanusa Timothy P. 
Published: March 2006

Abstract

In the slightly more than half a century that the organometallic chemistry of ruthenium has had time to develop, it has become clear that the metal's position as the ‘middle child’ of the Group 8 metals is richly reflected in its organometallic derivatives. That is, despite many similarities in the compounds of the iron–ruthenium–osmium triad, addition and elimination reactions of ruthenium, for example, are slower than those of iron but are more facile than those of osmium. Similarly, complexes with hydride and alkyl bonds are generally more stable for ruthenium than for iron, but the ruthenium compounds are often unstable or highly fluxional compared to analogous osmium species. Carbonyl cluster complexes are an important feature of organoruthenium chemistry, and mixed‐ligand carbonyl species with high nuclearity are known, in some cases with more than 10 ruthenium atoms. Interstitial carbides and nitrides are often encountered in ruthenium clusters, and carbonyl hydrides are of interest as hydroformylation catalysts (conversion of alkenes to aldehydes). The cyclopentadienyl ligand is found extensively throughout organoruthenium chemistry, and with a decomposition temperature around 600°C, the sandwich complex ruthenocene Ru(C
5
H
5
)
2
is among the most stable organometallic compounds known. The stability of ruthenocene and its derivatives allow them to be incorporated as labels into biomolecules such as peptides. Ruthenocene derivatives have also been studied as potential second‐order nonlinear optical materials, and they have played a central role in the development of 30 valence electron triple‐decker cations of the iron group. The high ligand field stabilization of Ru
II
enables combinations of π‐acceptor ligands together with even the hardest σ‐donors, such as carbonate, sulfate, or nitrate, and hence Ru
II
carbonyl and phosphine complexes are known with myriad coligand combinations having O, N, or S binding functionalities. In particular, the ability of the (η‐arene)Ru moiety to bind N‐ and O‐ligands has been used to complex various amines, imines, Schiff bases, and amino acids to generate diastereomeric salts, which can serve as chiral catalysts; they are valuable in stereoselective organic syntheses and in the production of biologically active compounds.
Selenium: Inorganic ChemistryBased in part on the article Selenium: Inorganic Chemistry by Bernt Krebs, Stefan Bonmann, & Illenora Eidenschink which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.
Authors: Atwood David A. 
Published: March 2006

AbstractSelenium is the first member of the group 16 elements O, S, Se, Te, and Po that shows some metallic character. The increasing metallic character in the series O, S, Se, Te, Po is reflected also in the lower electronegativity, in the less acid character of the oxides, and in the lower stability of the oxidation number +VI for selenium compared to sulfur. There is a large variety of compounds of SeII, SeIV, and SeVI with the electronegative elements N, O, F, Cl, and Br. Thus, there are six general types of compounds, and these will comprise the main sections in the article. They are cations, halides, oxides, haloselenates, oxohaloselenates, and the related compounds that form when both selenium and nitrogen are present in the molecule.
Selenium Proteins Containing Selenocysteine
Authors: Böck August 
Published: March 2006

AbstractSelenium is incorporated in the form of the nonstandard amino acid selenocysteine into selected proteins of organisms belonging to all three lines of descent. The majority of these proteins, which contain selenocysteine in the active site, catalyze oxidation–reduction reactions and are involved in numerous biochemical and regulatory processes, which are indispensable for the organism. Because of the higher chemical reactivity of selenocysteine in comparison to cysteine, selenoenzymes display a greatly increased rate of catalysis. Apart from its biochemical function, selenocysteine is also unique since its incorporation is DNA‐encoded and its cotranslational insertion follows a route independent in many features from the path of insertion of the 20 classical amino acids. Selenocysteine, therefore, can be considered the 21st amino acid.
Short‐Lived Intermediates
Authors: Almond Matthew J. , Jenkins Samantha L. 
Published: March 2006

Abstract
Methods for the generation and detection of short‐lived intermediates are discussed. These include flow systems (where a steady‐state concentration of the intermediate is monitored), flash photolysis (where the intermediate is studied in real time using a very fast detection method), and matrix isolation (where the intermediate is preserved by trapping in a solid, inert host at low temperature and where conventional spectroscopic methods are used for detection). Many of the classical experiments utilizing these methods are described, but the relevance to modern chemical studies is also emphasized. The spectroscopic methods used to detect short‐lived intermediates are considered. These include nuclear magnetic resonance (NMR), electron spin resonance (ESR), microwave, infrared (IR), Raman, and ultraviolet‐visible absorption and emission spectroscopies. It is shown that IR remains the method of choice for matrix‐isolation experiments whereas flash photolysis work tends to rely mainly upon electronic spectroscopic techniques. The use of IR spectroscopy, using tunable lasers, for flash photolysis work (at least for slightly longer‐lived intermediates) is discussed. Finally two case studies are considered in detail. These are the photolysis of metal carbonyls and the formation of unusual main group compounds at high temperatures. These studies exemplify the procedures that have been used to investigate short‐lived intermediates in inorganic chemistry.
Silver: Inorganic & Coordination ChemistryBased in part on the article Silver: Inorganic & Coordination Chemistry by W. Ewen Smith which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Mak Thomas C. W. , Zhao Xiao‐Li 
Published: March 2006

Abstract
The present review is a complete rewrite of the original article in the first edition. The new version provides concise and up‐to‐date information on the inorganic and coordination compounds of silver in oxidation states ranging from subvalent to Ag(IV). Literature coverage is extended to October 2004, and pertinent references are listed for the convenience of the interested reader.
The presentation is organized under the following headings: 1. Introduction; 2. Subvalent silver compounds; 3. Silver(I) compounds (under subheadings: 3.1 Halides and pseudohalides; 3.2 Phosphorus donor ligands; 3.3 Nitrogen donor ligands; 3.4 Oxygen donor ligands; 3.5 Chalcogen donor ligands; 3.6 Silver‐rich compounds); 4. Silver(II) compounds; 5. Silver(III) and silver(IV) compounds; 6. Catalysis. The structural features of the compounds are described, and specific examples are illustrated with five figures.

For the most important +1 oxidation state of silver, particular emphasis is placed on recent highlights and advances in new areas such as double and multiple salts of silver, silver(I) polyhedra with encapsulated acetylenediide (C
2
2−
) species (symbolized as C
2
@Ag

n

), argentophilic Ag(I)⋯Ag(I) interaction in supramolecular assembly, halide‐centered Ag

n

cages, mixed‐metal clusters, and silver‐rich chalcogenide supercluster complexes. Modern application of inorganic silver catalysts, of both achiral and chiral types, to organic synthesis is presented with selected examples from the recent literature.
Solids: Characterization by Powder DiffractionBased in part on the article Solids: Characterization by Powder Diffraction by Anthony K. Cheetham which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Vogt Tom 
Published: March 2006

Abstract
This review article covers recent developments in X‐ray and neutron powder diffraction with an emphasis on the complementary nature of these two condensed matter probes. After a short summary of the basics of X‐ray and neutron scattering, examples of ‘mesoscopic’ structure investigations (i.e. particle size, strain) are presented followed by state‐of‐the‐art combined neutron and X‐ray high‐resolution powder diffraction studies of ‘real’ catalysts. Neutron and X‐ray powder diffraction studies in magnetic fields are highlighted and the reemergence of the total scattering approach using pair‐distribution function (PDF) analysis within the context of ‘nanocrystallography’ is discussed. Modern examples of high‐pressure crystallography using X‐ray and neutrons are given. A short outlook considers future directions in light of nanoscience and new X‐ray and neutron sources.