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X-ray single-crystal study, molecular mechanics calculations, and calculations of the static nonlinear polarizabilities (β and γ) were performed for dicyanovinylbenzene and series of its mono- and dimethoxy-substituted derivatives. X-ray analysis has been done for dicyanovinylbenzene, its o- and p-methoxy- and 2,4-dimethoxy-substituted derivatives together with corresponding EFISH measurements of the β values for these compounds. Nonlinear polarizabilities were calculated for all series of the mono- and disubstituted methoxy derivatives of the parent compound with modified finite-field formalism that included calculation of polarization values versus static electric fields using semiempirical Hamiltonian, polynomial fit of all tensor elements of β and γ on the former data, and evaluation of the numerical instability of the calculations. All calculations were performed with optimized molecular geometries taken from X-ray data, molecular mechanics, ab initio, and semiempirical quantum chemical results. Good correlation was found between the predicted static and experimental molecular values of β. A factor of 2.0 was found to be a probable adjustment parameter to account for the solvent (1,4-dioxane) and dispersion (at 1064 nm) effects. Crystal packing analysis of the X-ray structures studied together with energetic calculations revealed the factors responsible for formation of centrosymmetric crystals. Only o-methoxydicyanovinylbenzene (also known as DIVA) forms acentric crystals (space group P21) among the experimentally studied compounds, and it was found that its molecular dipole moment orientation with respect to the polar crystal axis is close to the “optimal” for a manifestation of the high NLO responses.

The structural, electronic, and thermochemical properties of indium compounds which are of interest in halide transport and organometallic chemical vapor deposition processes have been studied by ab initio and statistical thermodynamic methods. The compounds reported include:  indium halides and hydrides (InF, InCl, InCl3, InH, InH2, InH3); indium clusters (In2, In3); methylindium, dimethylindium, and their hydrogen derivatives [In(CH3), In(CH3)H, In(CH3)H2, In(CH3)2, In(CH3)2H]; dimethylindium dimer [In2(CH3)4] and trimethylindium [In(CH3)3]; dehydrogenated methyl-, dimethyl-, and trimethylindium [In(CH3)2CH2, In(CH3)CH2, In(CH2)]; trimethylindium adducts with ammonia, trimethylamine and hydrazine [(CH3)3In:NH3, (CH3)3In:N(CH3)3, (CH3)3In:N(H2)N(H2)]; dimethylamino-indium and methylimino-indium [In(CH3)2(NH2), In(CH3)(NH)]; indium nitride and indium nitride dimer (InN, In2N2); indium phosphide, -arsenide, and -antimonide (InP, InAs, InSb). The predicted electronic properties are based on density functional theory calculations; the calculated thermodynamic properties are reported following the format of the JANAF (Joint Army, Navy, NASA, Air Force) Tables. Equilibrium compositions at two temperatures (298 and 1000K) have been analyzed for groups of competing simultaneous reactions.