Second-Order Non-Linear Optical Properties of Y-Type S-Triazine Based Derivatives

Abstract

Six modules (Y1~Y6) containing Y-type s-triazine based derivatives were optimized using density functional theory at B3LYP/6-31+G* level. On the basis of the optimized structure, electronic absorption spectrum was calculated with TD-DFT(TDB3LYP/6-31+G*) and the second-order nonlinear optical properties (NLO) were calculated with finite field (FF) method and coded programs. The results indicated that these molecules had good nonlinear optical properties with 106 order of magnitude a.u. (10-27 esu) of 0 value. Introducing different electron groups to the end of the tri-branched chain of this derivative would cause different results. Introduction of strong electron donating group would make a relatively large increase of u thus improving their second-order nonlinear optical properties, and making this derivative a good non-linear optical material.