用有限场和耦合微扰方法对N-氧化吡啶及其—NH_2,—NO_2单双取代衍生物非线性光学性质的研究

Finite Field, Time-dependent and Coupled Perturbed Hartree-Fock Calculation of Nonlinear Optical Properties of Pyridine N-Oxide and Its NH_2, NO_2-Substituted Derivatives

用 FF/PM3 ,FF/AM1 ,CPHF/PM3方法 ,对 N -氧化吡啶及其— NH2 ,— NO2 单双取代衍生物体系的非线性光学性质进行了理论研究 .结果表明 ,这类化合物具有很好的非线性光学性质 ,其中 2 -NH2 -5-NO2 -Py-1 -O和 2 -NH2 -4 -NO2 -Py-1 -O的二阶非线性光学系数均很大 ,而 2 -NH2 -5-NO2 -Py-1 -O三阶非线性光学系数最大 ,且略大于 1 -NH2 -4 -NO2

Crystals of pyridine N oxide and its substituted derivatives are the kinds of nonlinear optical materials. By means of Finite Field(FF)/PM3, time dependent and coupled perturbed Hartree Fock(CPHF)/PM3 calculations, the dipole moments, polarizabilities, first order hyperpolarizabilities and second order hyperpolarizabilities of pyridine N oxide and its NH 2, NO 2 substituted derivatives are obtained. The results show that this kind of compounds possess larger nonlinear optic properties, and suggest that these compounds are good candidates for nonlinear optical materials. 2 NH 2 5 NO 2 Py 1 O and 2 NH 2 4 NO 2 Py 1 O have the largest β, γ among them.[WT5HZ]