Y型均三嗪类衍生物三阶非线性光学性质研究

Thethird-order nonlinear optical properties of Y-type triazine-based derivatives

采用密度泛函理论B3LYP/6-31+G*方法对含Y型均三嗪类衍生物的6个分子(Y1-Y6)进行几何构型优化,对其最优构型采用TD-DFT(TDB3LYP/6-31+G*)计算电子吸收光谱,用有限场FF方法及自编程序计算三阶非线性光学(NLO)性质.结果表明,6个含Y型均三嗪类有机分子的三阶非线性光学系数g值为1010数量级个原子单位(10-30 esu),显示出良好的三阶非线性光学性能.在其三支链的末端引入不同的推、拉电子基团(Y2→Y6),对其电子光谱和三阶非线性光学响应具有明显的影响.引入强供电子基团,g增大幅度较大,有利于改善体系的三阶非线性光学性质,从而可获得良好的非线性光学材料.

Six modules （Y1-Y6） containing Y-type triazine-based derivatives were optimized using den- sity functional theory at B3LYP/6-31＋G＊ level. On the basis of the optimized structure, electronic ab- sorption spectrum was calculated with TD-DFT（TDB3LYP/6-31＋G＊ ） and the third-order nonlinear optical properties （NLO） were calculated with FF method and coded programs. The results indicate that these molecules have good nonlinear optical properties with 10^10 order of magnitude a.u. （10^-30 esu） of γvalue. Introducing different electronic groups （Y2→Y6） to the end of the three branched chains of this derivative would cause obvious influence on its electronic spectrum and the third-order nonlinear optical properties. Introduction of strong electronic group would make a relatively large increase of ythus impro- ving their third-order nonlinear optical properties, and making this derivative a good non-linear optical material.