【摘要】 在从头算RHF/STO-3G水平和RHF/6-31G水平上用CPHF方法计算了聚乙炔链的轴向线性极化率zαz和二阶超极化率zγzzz,最多计算到27个—C≡C—结构单元.讨论了拟合目标函数的选取和拟合函数的确定,以及适当选取拟合数据范围以外推出最可信的单元极化率和超极化率的极限值的问题.更多还原

【Abstract】 Ab initio restricted Hartree-Fock polyacetylene STO-3G and 6-31G calculations are reported for the linear longitudinal polarizability α_zz and the second hyperpolarizability γ_zzzz of the polyacetylene chain.The largest molecule we have calculated includes 27 —C≡C— units.The values per C≡C unit are accurately extrapolated to the inifinitely long chain.Various computational considerations such as the choice of fitting object functions,the fitting functions as well as the determination of the fitting data area are also discussed.更多还原