研究了一种包含西佛氏碱和萘酰亚胺新型材料的LB膜的制备,并采用二次谐波产生的方法研究了LB单层膜的二阶非线性光特性.这种化合物具有较大的二阶非线性极化率(χ(2)=1.51×10-9 esu).它的二阶非线性光特性起源于由苯乙烯形成的共轭π-电子体系.

Langmuir-Blodgett Film of a novel material which contain Schiff-base and naphthalimide has been made and characterized by using the surface pressure-area (π-A) isotherm line and UV-visible absorption spectra. The breakdown pressure of the monolayer was about 30 mN/m. The area occupied by each molecular was about 1.8 nm 2. The π-A isotherm line shown a steep solid field which demonstrated that this molecules could form a good monolayer on the water surface. The UV-visible absorption spectra shown that the molecule could be deposited onto solid substrate. The transfer ratio was kept in the range 1±0.1. The second-order nonlinear optical properties have been investigated by using second harmonic generation (SHG) technique in Langmuir-Blogett monolayer. The dependence of SHG intensity on the incident angle of fundamental is measured beam. A maximum in SHG intensity was obtained at the incident angle of 60°. The second order nonlinear optical susceptibility χ(2) is about 1.51×10-9 esu. The origin of second harmonic generation is attributed to the conjugation system formed by phenylenevinylene.