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The rotational isomeric state(RIS) model was constructed for poly(vinylidene chloride)(PVDC) based on quantum chemistry calculations.The statistical weighted parameters were obtained from RIS representations and ab initio energies of conformers for model molecules 2,2,4,4-tetrachloropentane(TCP) and 2,2,4,4,6,6-hexachlorohep-tane(HCH).By employing the RIS method,the characteristic ratio C∞ was calculated for PVDC.The calculated cha-racteristic ratio for PVDC is in good agreement with experiment result.Additionally,we studied the influence of the statistical weighted parameters on C∞ by calculating δC∞/δlnw.According to the values of δC∞/δlnw,the effects of second-order Cl―CH2 pentane type interaction and Cl―Cl long range interaction on C∞ were found to be important.In contrast,first-order interaction is unimportant.
The rotational isomeric state (RIS) model was constructed for poly (vinylidene chloride) (PVDC) based on quantum chemistry calculations. The statistical weighted parameters were obtained from RIS representations and ab initio energies of conformers for model molecules 2,2,4,4 -tetrachloropentane (TCP) and 2,2,4,4,6,6-hexachlorohep-tane (HCH) .By employing the RIS method, the characteristic ratio C∞ was calculated for PVDC. The calculated cha racteristic ratio for PVDC is in good agreement with experiment result. Additionally, we studied the influence of the statistical weighted parameters on C∞ by calculating δC∞ / δlnw. Based on the values of δC∞ / δlnw, the effects of second-order Cl-CH2 pentane type interaction and Cl-Cl long range interaction on C∞ were found to be important. contrast, first-order interaction is unimportant.