<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sulatha, M. S.</style></author><author><style face="normal" font="default" size="100%">Natarajan, U.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ab initio calculations of the geometry and polarizabilities of bisphenyls having aliphatic substituents</style></title><secondary-title><style face="normal" font="default" size="100%">International Journal of Quantum Chemistry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">ab initio</style></keyword><keyword><style  face="normal" font="default" size="100%">bisphenyl</style></keyword><keyword><style  face="normal" font="default" size="100%">optical anisotropy</style></keyword><keyword><style  face="normal" font="default" size="100%">polarizability</style></keyword><keyword><style  face="normal" font="default" size="100%">Polycarbonate</style></keyword><keyword><style  face="normal" font="default" size="100%">structure</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2011</style></year><pub-dates><date><style  face="normal" font="default" size="100%">APR</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">5</style></number><publisher><style face="normal" font="default" size="100%">WILEY-BLACKWELL</style></publisher><pub-location><style face="normal" font="default" size="100%">COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA</style></pub-location><volume><style face="normal" font="default" size="100%">111</style></volume><pages><style face="normal" font="default" size="100%">1092-1100</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Ab initio geometry optimization and polarizability calculations of a series of bisphenyls, which are the model compounds of chemically different polycarbonates using HF/6-31G and 6-31G** basis sets are presented. Calculated absolute value of the conformationally averaged optical anisotropy (&lt;gamma(2)&gt;) of diphenyl propane, a model analog of bisphenol A polycarbonate, is higher than the corresponding experimental value in the dilute solution phase. The calculations have reproduced the relative trend in the optical anisotropy for the different bisphenyl model compounds in a manner similar to those using semiclassical approach, by incorporation of the condensed phase polarizabilities and quantum chemically calculated geometry structure into the valence optical scheme. Individual contributions to the gas phase polarizability and optical anisotropy of the model compounds for various dihedral conformers, because of the presence of different aliphatic chemical groups, are correctly predicted by the calculations here. (C) 2010 Wiley Periodicals, Inc. Int J Quantum Chem 111: 1092-1100, 2011&lt;/gamma(2)&gt;&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">5</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">0.49</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Sulatha, M. S.</style></author><author><style face="normal" font="default" size="100%">Natarajan, Upendra</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of chemical substituents on the structure of glassy diphenyl polycarbonates</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Physical Chemistry B</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2011</style></year><pub-dates><date><style  face="normal" font="default" size="100%">FEB</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">7</style></number><publisher><style face="normal" font="default" size="100%">AMER CHEMICAL SOC</style></publisher><pub-location><style face="normal" font="default" size="100%">1155 16TH ST, NW, WASHINGTON, DC 20036 USA</style></pub-location><volume><style face="normal" font="default" size="100%">115</style></volume><pages><style face="normal" font="default" size="100%">1579-1589</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Polycarbonates offer a wide variety of physical property behavior that is difficult to predict due to complexities at the molecular scale. Here, the physical structure of amorphous glassy polycarbonates having aliphatic and cycloaliphatic chemical groups is explored through atomistic simulations. The influence of chemical structure on solubility parameter, torsion distributions, radial distribution function, scattering structure factor; orientation distributions of phenylene rings and carbonate groups, and free volume distributions, leading to interchain packing effects, are shown. The effect of the cyclohexyl ring at the isopropylidene carbon as compared to the effect of the methyl groups positioned on the phenylene rings results in a larger reduction in the solubility parameter (delta). The interchain distance estimated for polycarbonates in this work is in the range of 5-5.8 angstrom. The o-methyl groups on the phenylene, rings, as compared to a cyclohexyl ring, lead to higher interchain distances. The highest interchain distance is observed with a trimethylcyclohexylidene group at the isopropylidene carbon. Atomistic simulations reveal two different types of packing arrangement of nearest neighbor chains in the glassy state, one type of which agrees with the NMR experimental data The fundamental insights provided here can be utilized for design of chemical structures for tailored macroscopic properties.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">7</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">3.71
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