Cr. Moylan et al., DEFEATING TRADEOFFS FOR NONLINEAR-OPTICAL MATERIALS, Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals, 283, 1996, pp. 115-118
In order to be useful for electro-optic devices, nonlinear optical chr
omophores must be thermally stable, highly transparent, and have large
hyperpolarizabilities. Although these qualities are to some extent mu
tually exclusive, a small group of chromophores has been prepared that
meets the various criteria for applicability.