CRYSTAL-GROWTH OF A PROMISING NONLINEAR-OPTICAL MATERIAL - 2-AMINO-5-NITROPYRIDINIUM CHLORIDE

The experimental conditions of the synthesis and crystal growth of the 2-amino-5-nitropyridinium chloride (2A5NPCl) salt have been precisely determined, leading to the synthesis of large and optically clear cry stals. Synchrotron X-ray diffraction topography shows that the crystal line quality of the samples is good and that most of the defects (grow n-in dislocations) originate from the seed. This organic-inorganic pha se, which exhibits a high nonlinear optical efficiency (powder tests), a large transparency range (410-2000 nm), suitable thermal, chemical, and mechanical stabilities, and a bulky habit, is a promising materia l for nonlinear optics. (C) 1997 Academic Press.