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2-Amino-4-nitroaniline crystallizes in a noncentrosymmetric space group giving it significant potential for second-order nonlinear optical properties (NLO) in the bulk. The theoretically predicted NLO properties at the molecular level are confirmed using various methods like X-ray diffraction, conventional and polarized IR spectroscopy, thermal and elemental analysis.

The structures of the [{Os(PPh3)2(pap)}2(ca)](CIO4)2, [Os(PPh3)2(pap)(ca)], and [{Os(PPh3)2(CO)2}2(r-ca)] complexes are determined by X-ray crystallography. In the [{Os(bpy)2}(ca)](super 2+) and [{Os(PPh3)2(pap)2(ca)](super 2+) complexes, the chloranilate dianion is serving as a tetradentate bridging ligand.

Research has been conducted on the water-soluble secondary and tertiary phosphines. The synthesis of these phosphines with 1,1'-biphenyl backbones and dibenzophosphole moieties carried out via nucleophilic phosphination of sulfonated 2,2'-difluorobiuphenyl in the presence of potassium tert-butoxide has been investigated in aprotic dipolar solvents and the details are reported.

The mechanism of the photodecarboxylation of carbene and the electronic structure of 2,4-didehydrophenol by high level ab initio theory were studied. The thermodynamic role of carbon dioxide formation in the decarboxylation process was emphasized by estimating the heat of formation of triplet carbene. The presence of an intramolecular hydrogen bridge was observed in the x-ray structure analysis of diazo compounds. OH stretching vibrations of free carboxylic acids was also seen by matrix isolation spectroscopy.

The nucleophilic phosphination of FC6H4-4-SO3K, FC6H3-2,4-(SO3K)2 and FC6H4-2-SO3K with RPH2, where R = Ph, 2,4,6-Me3C6H2, 2,4,6-iPr3C6H2, in the superbasic medium DMSO/KOH yields chiral water-soluble secondary phosphines. The deprotonation of the secondary phosphines in DMSO/KOH gives phosphido anions which on alkylation yield mono- or bidentate tertiary phosphines. The electronic structure of the sulfonated fluorobenzenes and their reactivity towards nucleophilic phosphination are discussed using quantum chemical calculations.

The syntheses, crystal structures and solid-state nuclear magnetic resonance (NMR) spectra of trifluoro(methyl)(pyrrolidiniomethyl)silicate and trifluoro(phenyl)(pyrrolidiniomethyl)silicate were reported. The zwitterionic organofluorosilicates contain a pentacoordinate silicon atom and a tetracoordinate nitrogen atom. The results of solid-state NMR studies on tetrafluoro(pyrrolidiniomethyl)silicate, (3-ammoniopropyl)tetrafluorosilicate and trifluoro(phenyl)(pyrrolidiniomethyl)silicate were also described.

Force field measurements of the steric interactions in the different transition states in a Diels-Alder reaction waere undertaken to assess the contribution of electronic forces in stereoselection. The influence of electronic interactions was measured by comparing differences in the calculated and observed energy levels. The electronic interaction favors the formation of transition products in the cisoid conformation.

The crystal structure and optical and magnetic properties of the newly synthesized 4-cyanopyridinium hydrogensquarate monohydrate are analyzed by using single-crystal X-ray diffraction and other spectroscopic methods. The unusual red color of the compound in the solid state is shown to be due to a strong bathochromic shift of the charge transfer band within the stable layers formed by the (2HSq.2[H.sub.2]O) fragments.

2-Amino-4-nitroaniline crystallizes in a noncentrosymmetric space group giving it significant potential for second-order nonlinear optical properties (NLO) in the bulk. The theoretically predicted NLO properties at the molecular level are confirmed using various methods like X-ray diffraction, conventional and polarized IR spectroscopy, thermal and elemental analysis.

Two-phase phosphination of 2,2'-bis(halomethyl)-1,1'-binaphthyls with PH3 or in a protected-group synthesis afforded the first PH-functional phosphines with the 1,1'-biphenyl-2,2'-bis(methylene) and 1,1'-binaphthyl-2,2'-bis(methylene) backbones. These phosphines can form mononuclear and polynuclear compounds with transition-metal centers. One of the complexes was found to have various low-energy conformations, with some appearing to be capable of forming mononuclear transition-metal compounds.