GROWTH AND PERFECTION OF ORGANIC NONLINEAR-OPTICAL MATERIALS - KINETICS AND MECHANISM OF THE GROWTH OF N-(4-NITROPHENYL)PROLINOL (NPP) CRYSTALS FROM METHANOL AND TOLUENE SOLUTION

Organic nonlinear optical materials are difficult to prepare in single -crystalline form due to the inhibition of growth by the solvent. This yields poor growth characteristics which result in the development oi . strain and inclusions in the grown crystal. A study has been made of the growth mechanism and morphology of N-(4-nitrophenyl)prolinol usin g both a polar and nonpolar solvent. The results are used to define co nditions for the preparation of large crystals up to 2 x 0.8 x 0.8 cm( 3) of exceptionally high optical and structural perfection.