【摘要】 采用有限场方法和含时耦合微扰方法,在6-31+G*基组水平上并考虑了电子相关效应和色散效应的影响,计算了一水甲酸锂晶体的宏观二阶非线性光学极化率和二阶非线性光学系数。其中非线性光学系数d31和d32与Roberts报道的相符,而另一个系数d33则比文献值大。计算结果还表明,在非共振情况下,电子相关效应对非线性光学极化率的影响远远超过了色散效应,同时表明Roberts报道的非线性光学系数比Singh等人报道的更为合理。更多还原

【Abstract】 The second-order nonlinear optical coefficients of lithium formate monohydrate crystals (LFM) have been calculated by both the finite-field MP2 approach and the coupled perturbed Hartree-Fock method at the level of 6-31+G* basis set with the considerations of electron correlation and frequency dispersion. Two of the coefficients, d31 and d32, agree well with the experimental values but another one, d33, is overestimated. The influence of electron correlation on b is much larger than that of frequency dispersion on b. The set of NLO coefficients reported by Roberts is more reasonable than that by Singh et al.更多还原