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In recent years, research in organophosphorus chemistry has mainly focused in designing newer and better phosphorus ligands for synthesizing novel metal complexes with improved catalytic activities. Aminophosphines [tricoordinate phosphorus(III)-nitrogen systems] are considered as versatile compounds owing to the presence of nitrogen centres which, in principle, can influence additional reactivity features. They are quite sensitive to air and moisture due to the presence of polar P-N bond(s). In spite of this, research in aminophosphine chemistry is gaining momentum day-by-day and this is due mainly to one reason: their rich behaviour as ligands in metal complex chemistry and subsequently in catalysis. Their role as synthons in inorganic heterocyclic chemistry has also helped produce new types of heterocycles. In this paper, the chemistry of simple acyclic aminophosphines (synthesis, characterization, reactivity and applications) is covered and particular focus is given to their ability to form chalcogenides along with their role played as ligands in coordination chemistry and as synthons in inorganic heterocyclic chemistry.

NaLaSrNb2Co09 brown 3.967(5) NaLaSrNb2Ni09 gray 3.966(3) NaLaSrNb2Cu09 brown 3.978(5) NaLaSrNb2Zn09 white 3.988(4) CsLaSrNb2Cu09 gray 7.846(5) CsLaSrNb2Zn09 white 7.837 (8) 3-D perovskite 4.00 3-D perovskite 2.96 3-D perovskite 1.70 3-D perovskite 30.49(2) 2-D perovskite 1.68 30.66(3) 2-D perovskiteThe oxides possessing perovskite (CaTi03)-related structures are indeed legion.* 1 Besides the stoichiometric (ABO3) perovskites and their ordered variants (e.g., A2BB'06, AsBB^Oci), quite a few defective perovskites (e.g., ABO3-*) forming a variety of perovskite superstructures are known.2 Furthermore, a number of layered oxides, such as the Ruddlesden-Popper phases3 and the Aurivillius phases,4 which could be regarded as derivatives of the perovskite structure, are also known. These materials contain two-dimensional (2-D) perovskite slabs of composition [A"-iB"03"+i] as one of the units building the layered structure. The A"-iBn03"+i units may be thought of as derived by slicing, as it were, the three-dimensional (3-D) perovskite structure along one of the three cubic directions.5Considering the large number of perovskite-related oxides known at present,1 one would feel that all the possible combinations of elements that would give perovskite-related oxides have already been exhausted. Fortunately, this is not so, because time and again, novel members are being added to the growing list of perovskite-related phases. A typical example is the discovery of superconducting YBa2Cu307, which possesses a unique vacancy-ordered perovskite structure.6As a part of our continuing efforts to synthesize novel layered oxides exhibiting interlayer chemistry,7 we investigated the formation of perovskite-related phases for the compositions ALaSrNb2Mn09 (A = alkali metal and M = Co, Ni, Cu, or Zn). To our surprise, the compositions adopted a cubic (3-D) perovskite structure when A = Na and a layered (2-D) perovskite structure, related to CsCa2Nb30io,8 when A = Cs. This result, which is reported in this communication, reveals the interesting possibility of tailoring perovskite (ABO3) oxides into 2-D or 3-D structures by the appropriate choice of A-site cations. Furthermore, the strategy can be extended to synthesize layered perovskite oxides of variable thickness by choosing appropriate chemical compositions. We believe that the present f Contribution No. 1075 from the Solid State and Structural Chemistry Unit.

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LQES-Vivência do LQES-Biblioteca-Química do Estado Sólido Solid state chemistry has become a vital component of mainstream chemistry and materials. Structure, Synthesis, Properties, Reactivity and Materials Design Buy New Directions in Solid State Chemistry: Structure, Synthesis. Solid State Chemistry Synthesis Properties-Orimikr.ninja Mesoporous organosilica-Wikipedia, the free encyclopedia Status and Future Developments of Solid State Chemistry and Materials",. of important areas discussed in this session include the reactivity of mineral complex mineral structures are not often considered by solid state chemists in their. Synthesis of new materials and characterization of their properties is at the heart.