多取代巴比妥酸系列衍生物三阶非线性光学性质的理论研究及分子设计

在 ZINDO方法基础上 ,按完全态求和 (SOS)公式编制了计算三阶非线性光学系数γijkl的程序 ,研究了多取代巴比妥酸系列衍生物分子的结构 ,光谱和三阶非线性光学系数 γ(- ω;- ω,ω,ω) ,γ(0 ;0 ,0 ,0 ) .除了通常的 D- π- A结构外 ,还研究了 D- A-D结构 .对这些 NL O生色团分子的结构与三阶 NLO性质的关系给予系统的理论研究 .考察了给体 ,桥 ,受体变化 ,D- π- A结构及 D- A- D结构对 γ的影响 ,结论是 :1 .氧代巴比妥酸受体三阶 NLO系数高于硫代巴比妥酸受体 . 2 .芳基给体取代基与烷基给体取代基相比 ,不仅热稳定性高于后者 ,而且 γ值亦高于后者 ,从而设计了一系列有实际应用价值的热稳定性好、有优良非线性光学性质的分子

Theoretical Study on the Device of Molecules with Third-order NLO Susceptibility on a Series of Multi-substituent Babituric Acid and its Derivatives

On the basis of ZINDO, the program for calculating the third order NLO susceptibility γ ijkl was devised according to the sum over state expression. The structure, electron spectra, γ(-ω;-ω,ω,ω ), and γ (0;0,0,0) of a series of multi substituent babituric acid derivative molecules were studied. The influence of donor π conjugated bridge, acceptor, D π A, D A, D A D structure on the γ was examined. The conclusion is that, 1. the γ values of oxo babituric acid higher than thio babituric acid. 2. Thermal stability and the values of γ of the aryl donor substituent enlarge as compared with the alkyl donor substituent. At last, we designed excellent NLO materials which have practical applications with bigger γ and good thermal stability.