Abstract

Organic nonlinear optical (NLO) crystals have a large nonlinear coefficient. However, the red shift of the cut-off wavelength caused by large organic π-conjugated molecule systems, the strong dispersion resulting from the large birefringence caused by layer packing, and the difficulties of processing owing to their poor mechanical properties as well as other factors, all these have greatly hindered the use of organic materials. Now, the organometallic complex has the advantages of organic crystals to make up for their drawbacks, which greatly optimize the comprehensive properties of the organic crystals. Minhua Jiang et al. announced in 1985 that the organometallic complex is a potential field for the exploration of new NLO materials, and they proposed the double radical structure model theory.⁵ Using this theory, we have explored a series of highly efficient SHG materials such as BTCC,² TSCCC,³ etc.

© 1993 Optical Society of America