bluuebunny/crossref_metadata_2025_split huggingface dataset:
Borides: Solid‐State Chemistry
Authors: Lundström Torsten 
Published: December 2011

AbstractBoron forms compounds with most other elements. In addition to numerous binary and ternary compounds with metals – the true borides – boron forms related compounds with carbon, silicon, nitrogen, phosphorus, arsenic, oxygen, sulfur, and selenium. These related compounds are formed by elements more electronegative than boron and cannot therefore be denoted as borides. They display, however, similar properties and structures as borides, and are, therefore, included in the present article.Borides are to some extent related to carbides and nitrides. All three groups of compounds are compounds between small nonmetal and larger metal atoms. They are occasionally denoted interstitial compounds, since the small nonmetal atoms often occupy the interstices between the metal atoms in metal‐rich compounds. In boron‐rich compounds, however, boron octahedra or icosahedra form a continuous three‐dimensional network. Most borides are characterized by high melting points, extreme hardness, brittleness, high chemical stability, and high inertness toward reactive metals.The borides are nonmolecular compounds and knowledge of the crystal structure is consequently of very high importance to characterize a boride phase. The structural principles of mainly the binary and ternary borides are described in the article. There are a total number of at least 950 binary and ternary borides known at present.The chemical bonding in borides has evident contributions from covalent, ionic as well as metallic bonding, which explains some of the unique properties of the borides. As a rule, phases containing a large proportion of boron are semiconductors, while those with a lower proportion of boron are metallic conductors. TiB2and MgB2are good metallic conductors while MeB6phases are either semiconductors or metallic conductors depending on the metal. Many theoretical calculations are available, in particular of diborides, including the recently discovered superconductor MgB2.The uses of borides and related compounds are mainly based on the their hardness, chemical inertness, and magnetic and electrical properties. A few examples may be mentioned. B4C and cubic BN are used as abrasives, B4C and hexaborides as surface coatings, and CaB6as deoxidation agent in some metallurgical processes. TiB2is used in the production of vaporization boats for aluminum. It is also used in the industrial production process for aluminum owing to its high electrical conductivity and inertness toward liquid aluminum. Nd2Fe14B is the strongest permanent magnetic material known. Large single crystals of YB66are used for monochromating synchrotron radiation.
Boron HydridesBased in part on the article Boron Hydrides by James T. Spencer which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Hosmane Narayan S. , Maguire John A. 
Published: December 2011

Abstract
Boranes are hydrides of boron in which BH groups occupy the apices of electron‐deficient clusters. The term ‘electron deficient’ arises from the fact that boron has more valence orbitals than it does valence electrons. The consequence of this imbalance is that the clusters are stabilized by extensive multicentered bondings. The relationships between cage structures and the number of cage electrons are discussed for boranes and their extension to heteroboranes, where one or more BH units are replaced by isolobal main group or transition metal moieties. General synthetic methods and reactivities of the heteroboranes are also discussed.
Boron: Inorganic Chemistry
Authors: Schubert David M. , Brotherton Robert J. 
Published: December 2011

AbstractBoron is unique among the elements and displays remarkable chemistry in all of its compounds. It is widely distributed at low concentrations on the Earth and is virtually always found bound to oxygen in its natural forms. Boron enters into the life cycle of and is an essential element for plants and animals. The vast majority of industrial uses of boron on a weight basis also involve boron–oxygen compounds, including important mineral sources, metal borates, boric acid, boric oxide, and boric acid esters. These find large‐scale applications in many industries, most notably in the manufacture of glass and other vitreous materials. Boric acid is a weak Lewis acid and does not display Brønsted acidity in aqueous solution. The condensation of B(OH)3and B(OH)4−species to form polyborates in relatively concentrated borate solutions has important implications for the solubilities and other solution properties of metal and nonmetal borate salts. Boric acid reacts with alcohols and other hydroxyl group‐bearing compounds to form esters, which find many industrial uses. Reversible borate ester crosslinking leads to polymer gel formation and provides the basis for the essential biological role of boron. Nonoxide boron compounds also have important industrial uses. These include refractory compounds, such as boron carbide, boron nitrides, boron phosphides, elemental boron, and metal–boron alloys, as well as nonrefractories, such as the boron halides. Nonrefractory boron–phosphorus and boron–sulfur compounds and the boron subhalides are yet to find significant industrial use, yet, nonetheless exhibit fascinating chemistries.
Boron: Organoboranes
Authors: Jäkle Frieder 
Published: December 2011

AbstractThis chapter provides an overview of recent developments in the highly interdisciplinary field of organoboron chemistry. The most important routes for the synthesis of organoboranes via transmetallation, hydroboration and other boration reactions, as well as CH activation are outlined. The various classes of organoboranes thus accessible are presented according to the nature of the organic substituents. Special emphasis is given to applications of organoboranes. For example, the development of new chiral organoboranes that are commonly used in enantioselective synthesis is shown. Moreover, the importance of fluorinated arylboranes as highly efficient Lewis acid catalysts and cocatalysts for organic transformations and polymerization reactions is discussed. The use of triarylboranes and related compounds as electronic and optical materials for device applications, and as sensors for the recognition of anions and neutral Lewis bases is also described in detail.
Boron: Polyhedral CarboranesBased in part on the article Boron: Polyhedral Carboranes by Robert E. Williams which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Hosmane Narayan S. , Maguire John A. 
Published: December 2011

Abstract
Carboranes are compounds in which carbon, boron, and hydrogen atoms are present in polyhedral cages. The cages are stabilized by multi‐centered bonds, which gives the carboranes unique chemical and structural properties. Many of these compounds are chemically and thermally stable enough to allow their use as boron delivery agent for boron neutron capture therapy (BNCT) in cancer treatment and as molecular assemblies.
Carbon: Inorganic ChemistryBased in part on the article Carbon: Inorganic Chemistry by R. Bruce King which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Friščić Tomislav , MacGillivray Leonard R. 
Published: December 2011

Abstract
The article provides a brief and general overview of the chemical and physical properties of carbon, as it relates to inorganic chemistry. Several allotropic forms of carbon are described, with general properties discussed. The characteristics and synthetic methods for the preparation of simple compounds involving carbon or carbon and hydrogen with halogens, oxygen, sulfur, as well as nitrogen, are provided. In addition, recent developments in supramolecular chemistry to construct ladder‐like carbon frameworks are outlined.
Carbonylation Processes by Homogeneous CatalysisBased in part on the article Carbonylation Processes by Homogeneous Catalysis by George G. Stanley which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Parr M. L. 
Published: December 2011

Abstract

This article reviews homogeneously catalyzed carbonylation reactions with particular emphasis on catalytic hydroformylation using cobalt, rhodium, platinum, and palladium complexes. The carbonylation of methanol based on rhodium and iridium complexes (Monsanto and Cativa
™
processes, respectively) is also discussed. Examples of the utility of carbonylation in the synthesis of complex molecules are given.
Cobalt:B12Enzymes & Coenzymes
Authors: Kräutler Bernhard 
Published: December 2011

AbstractThe most prominent biological role associated with cobalt concerns vitamin B12, its natural variants, and its coenzyme forms. The B12‐derivatives are cobalt complexes of the unique and remarkably complex corrin ligand that belong to the larger class of the tetrapyrrolic natural compounds. The ‘antipernicious anemia factor’ vitamin B12and its cofactor forms are, first of all, required for human and animal health. However, except for the higher plants, all forms of life appear to depend upon the natural variants of vitamin B12. The main chemical reactivities of the corrinoids (needed to fulfill their essential biological roles) may reflect their possible corresponding chemical contributions to the development of the early stages of life on earth. Indeed, the corrinoids play a particularly basic role in carbon metabolism in microorganisms, which also are the only natural sources of the B12‐derivatives. Microorganisms have developed extraordinary means for the biosynthesis, and for the regulation of the biosynthesis of the B12‐derivatives, in order to cope with the structural and functional complexity of these tetrapyrrolic cobalt‐compounds, while most (other) forms of life have evolved intricate strategies for the economic and efficient uptake and transport of the corrinoids. The known cofactor functions of the cobalt‐corrinoids are due to their extraordinary organometallic chemistry and their redox chemistry under physiological conditions: Coenzyme B12, methylcorrinoids, and reduced corrinoids are the cofactors in various important and unique organometallic enzymes, whose intricate structural and mechanistic properties are the current focus of strong and broad research activities. The essential role of the corrinoids in the remarkable organometallic paths of carbon fixation and further carbon metabolism in anaerobic microorganisms has attracted particular attention. Vitamin B12and its derivatives thus hold an important position in all of the life sciences and are at the center of particular interdisciplinary interest from such diverse areas as medicine, biology, chemistry, and physics.
Coordination & Organometallic Chemistry: Principles
Authors: Crabtree Robert H. 
Published: December 2011

Abstract
The title topic is reviewed. Under coordination chemistry, special attention is given to Werner complexes, the trans effect, soft and hard ligands, crystal and ligand field (LF) models, together with oxidation state and coordination number. Under organometallic chemistry, the main topics include electroneutrality, back bonding, the 18‐electron rule, and effects of complexation.
Copper Proteins with Dinuclear Active SitesBased in part on the article Copper Proteins with Dinuclear Active Sites by Konrad Lerch which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.
Authors: Decker Heinz 
Published: December 2011

AbstractCopper proteins with dinuclear active sites comprise proteins with different structures and functions. The phenoloxidase, tyrosinase, and catecholoxidase are responsible for browning by starting the synthesis of melanin. These enzymes are involved in the primary immune response in invertebrates, plants, fungi as well as in the sclerotization of arthropods. The respiratory proteins hemocyanins are responsible for oxygen transport in some arthropods and molluscs. However, they can be converted to enzymes exhibiting phenoloxidase activity. Based on X‐ray structures of hemocyanins and a catecholoxidase, large parts of folding motifs are very similar although the sequence identities are far below 30%. A model for the activation process of phenoloxidase activity is presented.
Copper Proteins with Type 1 SitesBased in part on the article Copper Proteins with Type 1 Sites by Edward N. Baker which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.
Authors: Hart P. John , Nersissian Aram. M. , George Serena DeBeer 
Published: December 2011

AbstractCopper Proteins with Type 1Sites is a general review that focuses on single‐domain proteins that bind ‘blue’ or ‘type 1’ copper. Larger, multidomain proteins that contain type 1 copper in addition to other types of copper centers are not discussed at any length in this article. Blue copper proteins are so named because in solution they are a brilliant blue/azure color when the copper ion is in its Cu(II) oxidation state. The bright blue color comes from a charge transfer (CT) between Cu(II) and the sulfur (thiolate) of a ligating cysteine residue. Because of this intense color, type 1 copper proteins were among the first to be isolated because they could be tracked easily during purification processes. This, together with their unique spectroscopic properties that have no parallel in small‐molecule copper complexes, has made them the subject of intense study over the last 35 years. This article focuses on three main aspects of type 1 copper proteins: (1) their occurrence, distribution, and classification based on analyses of genomic and expressed sequence tag data; (2) their three‐dimensional structures as determined by the well‐established tools of single‐crystal X‐ray diffraction and nuclear magnetic resonance (NMR); and (3) their electronic, spectroscopic, and electron‐transfer properties.
Dinuclear Organometallic Cluster Complexes
Authors: Kiss Gabor , McDonough James Eric , Weir John J. , Hoff Carl D. 
Published: December 2011

AbstractMetal–metal bonding in dinuclear complexes plays a key role in inorganic and organometallic chemistry. It is the basis for development of polymers and clusters derived from this simple unit. Its chemistry now approaches the ‘functional group’ status, typically used in organic chemistry for classes of compounds. However, owing to the array of metals and oxidation states involved, a wide range of structures, reactions, and properties are observed for this important class of compounds. This article introduces the topic of metal–metal bonded complexes and attempts to outline the synthetic strategies used to prepare metal–metal bonded complexes, some of their characteristic properties and reactions, as well as to provide a brief introduction to historical development and emerging directions of this central area of inorganic chemistry.
Electron Transfer Reactions: TheoryBased in part on the article Electron Transfer Reactions: Theory by Roderick D. Cannon which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.
Authors: Matyushov Dmitry 
Published: December 2011

AbstractThis article discusses the progress in the field of electron‐transfer theory over the period of about 50 years since early 50s marked by the development of theories of radiationless transitions in molecules in the gas phase and the Marcus theory of electronic transitions between ions in solution. The article starts with the classification of electron‐transfer reactions in terms of reaction mechanisms and the extent of electronic delocalization. This is followed by the outline of the picture of intersecting parabolas due to Marcus, which defines the activation barrier for nonadiabatic electron transfer. The rate of nonadiabatic electron transfer strongly depends on electronic coupling between the donor and acceptor states. The Mulliken‐Hush theory, along with its recent generalizations, provides coupling from spectroscopic observables. The success of electron‐transfer theories has largely been supported by the connection between thermal rates and optical spectroscopy. The activation barrier can be obtained from optical spectra by using the band‐shape analysis discussed next. This is followed by the overview of the inverted region of electron transfer and the consequences of introducing nonparabolic free energy surfaces of electron transfer in polarizable systems. The advent of ultrafast spectroscopic techniques opened up a new avenue in electron‐transfer research related to the effects of polarization dynamics on the reaction rate. Measurements at varying pressure allow one to introduce an additional thermodynamic variable probing the activation barrier. The article concludes with a brief account of magnetic effects in electron transfer.
Electronic Structure of Main‐Group CompoundsBased in part on the article Electronic Structure of Main Group Compounds by Jeremy K. Burdett which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.
Authors: Frenking Gernot , Lein Matthias 
Published: December 2011

AbstractQuantum chemical research has made significant progress in the understanding of the electronic structure and the nature of the interatomic interactions yielding chemical bonds in molecules. Ad hoc models of chemical bonding have been complemented or replaced by more sophisticated approaches for analyzing the bonding situation in molecules. The new methods build a well‐defined bridge between the heuristic bonding models using pictorial approaches and the physical mechanism of a chemical bond. Bonding models can be examined with quantum chemical methods, which show that chemical intuition and physics do not exclude each other. The paper describes important methods using charge and energy partitioning approaches, which are helpful and widely used in modern theoretical inorganic chemistry for understanding the electronic structure and bonding situation of main‐group compounds. The application of the methods to representative main‐group compounds is described and the results are critically discussed.
Electronic Structure of Organometallic Compounds
Authors: Albright Thomas A. 
Published: December 2011

Abstract

A brief treatment of the concept of orbital interaction is given, particularly in reference to the transition metal‐ligand bond. This is then applied to the σ splitting pattern for the ML

n

series where
n
= 6, 5, 4 (square planar and tetrahedral), 3, and 2 cases. Here M is a transition metal and L is a generic ligand with a σ donor function. A description is given for how the splitting pattern is modified when one or more of the ligands have π acceptor or donor functions. Several examples illustrate how symmetry can sometimes create modification to the normal electron counting rules. A detailed discussion is given of how to create the important valence orbitals of an ML

n

fragment and several examples are given of their use to build up the orbitals of large organometallic molecules. Finally, a detailed discussion is given of the construction and use of the isolobal analogy.
Gallium: Inorganic ChemistryBased in part on the article Gallium: Inorganic Chemistry by Andrew R. Barron which appeared in theEncyclopedia of Inorganic Chemistry, First Edition.
Authors: Banger Kulbinder Kumar , Hepp Aloysius F. 
Published: December 2011

AbstractAn overview of the inorganic chemistry of gallium and its compounds is reported in detail with an attempt to bring up to date current studies in this field. In addition, the use of various Ga related alloys as either binary or ternary semiconducting material for bulk, thin film, and nanotechnology is reported in detail pertaining to their synthesis, properties, and application. The chemistry of Ga inorganic and coordination derivatives is also reviewed and discussed.
Gallium: Organometallic ChemistryBased in part on the article Gallium: Organometallic Chemistry by Andrew R. Barron which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Robinson Gregory H. 
Published: December 2011

Abstract
The organometallic chemistry of gallium has experienced substantial growth over the past decade. Much of this work concerned the development of the organometallic chemistry of compounds containing GaGa bonds. This would include simple dimeric compounds, gallium ring compounds, and small gallium clusters. This chapter will discuss the synthesis and structural aspects of these compounds.
Germanium: Organometallic Chemistry
Authors: Banaszak Holl Mark , Peck David R. 
Published: December 2011

AbstractThis article provides an overview of the organometallic chemistry from 1994 to 2004. Major advances in the formation and breaking of GeC bonds are discussed, as are advances in the physical characterization of these compounds. Recent advances in the formation of organogermanium species containing multiple bonds to germanium and the formation of germanium‐centered radicals and cations are delineated. Applications to the synthesis of germanium‐containing polymers are overviewed.
Gold: Inorganic & Coordination Chemistry
Authors: Vittal Jagadese J. , Puddephatt Richard J. 
Published: December 2011

Abstract
Gold compounds are finding new applications in catalysis, medicine, and molecular materials, based on their reactivity and unusual physical and chemical properties. The theoretical basis of the unique properties of gold compounds continues to develop rapidly and provides a constant challenge for synthesis of new types of gold compounds. This chapter gives an overview of these exciting developments while giving an overview of the modern inorganic chemistry of gold.
Hydroboration CatalysisBased in part on the article Hydroboration Catalysis by Kevin Burgess & Wilfred A. van der Donk which appeared in the
Encyclopedia of Inorganic Chemistry, First Edition
.
Authors: Vogels Christopher M. , Westcott Stephen A. 
Published: December 2011

Abstract
Among the most significant advances in organic synthesis over the past few decades are those associated with the development of transition metal complexes for their use as catalysts in organic reactions. The discovery that transition metals can also be used to catalyze the addition of BH bonds to unsaturated substrates has provided the synthetic chemist with another valuable tool. This review examines recent advances in the field of catalyzed hydroborations and their applications in organic synthesis.
Hydrogenation & Isomerization of Alkenes
Authors: Jardine Fred H. 
Published: December 2011

AbstractAlkenes are isomerized by complexes of late, second or third series transition metals. This occurs either by successive β‐hydride abstraction reactions or, more rarely, by a π–allylic mechanism. Both decyclization and annulation reactions of strained, cyclic hydrocarbons are catalyzed by these complexes. Palladium complexes are active catalysts for the Cope‐ and Claisen rearrangements. Homogeneous, catalytic hydrogenation can occur via three possible routes. Ruthenium complexes catalyze transfer hydrogenation. Catalyst modifications can be made to minimize by‐product formation during hydrogenation or deuteriation.
Indium: Organometallic Chemistry
Authors: Kumar Banger Kulbinder 
Published: December 2011

AbstractAn overview of the chemistry of organoindium compounds containing at least one InC bond over the last ten years is reported in detail. In particular, the synthesis, characterization, properties of homoleptic and heteroleptic organoindium derivatives, organoindium(0), (I), and (II) compounds, and in addition anionic compounds are also reported. Furthermore, the use of organoindium compounds for thin film, nanotechnology, and organic synthesis is discussed.