Characterization of directed ammonium malate single crystals grown by Sankaranarayanan–Ramasamy method

Abstract

Ammonium malate, an organic nonlinear optical single crystal, has been grown to a dimension of 50 mm length and 20 mm diameter by uniaxial solution-crystallization method of Sankaranarayanan–Ramasamy (SR). The growth conditions and experimental details of the grown crystals have been presented. The crystalline perfection of the grown crystals has been evaluated by high-resolution X-ray diffraction technique and the results reveal that the crystal quality of SR grown crystal is better than the conventional method grown crystal. The growth features in SR grown crystal have been analyzed by chemical etching technique and well-defined triangular etch hillocks have been observed. The mechanical property of the grown crystal has been analyzed by Vickers microhardness method and it reveals that the grown crystal is moderately harder material. Ammonium malate crystal possesses lower cut off wavelength at 230 nm. It enables good optical transmission of the second harmonic generation of Nd:YAG laser and other applications in the blue-violet region. The second harmonic generation of the grown crystal has been confirmed by the Kurtz powder technique.