Crystal structure and nonlinear optical properties of stilbazolium derivatives having shortened cut-off wavelength

Aiming at the shortening of absorption cut-off wavelength of inerocyanine, we prepared several stilbazoliuni derivatives. Their absorption bands are appreciably shifted to shorter and some of them have large SHG efficiencies. Among them, cyanostilbazolium p-toluenesolfonate complex has an absorption cut-off around 400nm and its nonlinear optical coefficient d33 is four times larger than d14 of POM.