Abstract: A charge-transfer salt exhibiting photosensitivity and nonlinear optical property has been synthesized from tungstosilicic acid and N-methylpyrolidone and characterized by elemental analysis and IR spectrometry. The photosensitivity of the compound has been studied by diffuse reflectance electronic spectrometry and ESR measurement. The nonlinear optical property of the compound is determined by powder method. The results show that electron can be transfered between organic species and the anion under light irradiation. The compound exhibits the second- and third-order nonlinear optical properties. The third-harmonic generation intensity and the thir-dorder susceptibility of the compound measured by secondharmonic generation technique relative to a KDP crystal were estimated to be I=0.85I_KDP and χ⁽³⁾=3.6?10^-12esu, respectively.

Key words: tungstosilicic acid, charge-transfer salt, photosensitivity, nonlinear optical property