ORGANIC NONLINEAR OPTICAL MATERIAL

摘要

PURPOSE:To obtain a large single crystal which has a large secondary nonlinear optical constant and short visible absorption end and to provide stability in the atm. to the above material by consisting the material of ortho-alkoxybenzol- malononitrile. CONSTITUTION:This material consists of the ortho-alioxybenzol-malononitrile expressed by the formula I, where an alkoxyl group of 1-4C is preferable and more particularly a methoxy group is preferable as the alkoxyl group expressed by R. The ortho-alkoxybenzol-malononitrile has an electron- withdrawing group and electron-donating group on both sides of a pi electron conjugation chain in the ortho position and, therefore, has large secondary nonlinear molecular sensitivity; in addition, the crystal has no symmetrical centers of inversion because of the asymmetry of the molecules. This material is thereby provided with the large nonlinear optical constant and the short absorption end. The large single crystal is thus obtd. and the phase matching is possible. The material is stable in environment.