对硝基二苯乙炔系列衍生物的二阶非线性光学性质的理论研究

在ZINDO方法基础上,按完全态求和(SOS)公式编制了计算分子二阶非线性光学系数β_ijk和β_μ的程序,研究了对硝基二苯乙炔系列衍生物的结构和非线性光学性质,考察了分子共轭链长和给电子基团对β_μ的影响.结果表明,对硝基二苯乙炔系列衍生物上连有推电子基团有利于增大二阶光学非线性,扩大共轭范围也有利于增大二阶光学非线性,但对透明性则影响不大.

A Theoretical Studies on Nonlinear Second-order Optical Properties of p-Nitrobis(phenylethynyl)benzene Series Derivatives

On the basis 0f ZINDO methods, according t0 the sum-over-states expression, wedevised the program for the calculati0n of the nonlinear sec0nd-order optical susceptibilitiesP,j* and g# of molecules, and studied the structures and nonlinear optical properties of p-nitrobis(phenylethynyl)benzene series derivatives. The influence of the molecular conjugatedchain lengths, and the d0n0r to g. was examined. lt is c0ncluded that the donor substitutedon p-nitr0 bis(phenylethynyl)benzene series derivatives facilitates the n0nlinear second-orderoptical susceptibility. Extending the c0njugated area, the nonlinear second-order optical sus-ceptibility increases too, but the transparency has not been greatly influenced.