Synthesis, crystalline perfection, optical and dielectric studies on metal-organic tri-allylthiourea cadmium chloride (ATCC) nonlinear optical single crystal by solution growth technique

A family of optically negative organometallic, allylthiourea complex single crystals such as ATCC, ATCB, ATMC and ATMB are extensively studied for their application in nonlinear optical (NLO) devices. In this category of materials, allylthiourea serves as double ligand to form co-ordination complexes with metals. Allylthiourea cadmium chloride single crystals were grown by solvent evaporation and temperature lowering techniques in an optimized pH value. X-ray rocking curve of the grown crystal was recorded with high resolution multicrystal X-ray diffractometer. The obtained single sharp peak reveals that the grown crystal specimen is free from structural grain boundaries. The grown crystal has wider transparency window with the lower cut-off wavelength at 285 nm. The refractive index measurements at three different laser wavelengths (633 nm; 1.72503, 825 nm; 1.71053 and at 1061 nm; 1.70085) indicate decrease in index value with increasing laser wavelength. The Kurtz and Perry powder technique was used to confirm the NLO property of the as grown crystals. The dielectric constant of the as grown crystal is measured for various frequencies and temperatures and chemical etching analysis is also carried out and the obtained results are presented. (C) 2012 Elsevier B.V. All rights reserved.