Synthesis, spectral and thermal properties of non-linear optical crystal ZnMg(SCN)4

Single crystals of zinc magnesium tetra thiocyanate [ZnMg(SCN)(4)], a bimetallic thiocyanate complex, were grown by slow evaporation solution growth technique at room temperature. The bright, transparent and colourless crystals have well defined faces. The grown crystals were characterized through elemental analysis, powder X-ray diffraction (XRD), thermogravimetric (TG) and differential thermal analysis (DTA), differential scanning calorimetric analysis (DSC), Fourier Transform Infra red (FTIR) and Optical studies. The elemental analysis confirms the stoichiometry of the synthesized crystals. The compound crystallizes under monoclinic structure with lattice parameters a = 10.055 angstrom, b = 7.44 angstrom, c = 6.00 angstrom and beta = 90.113 degrees. The TGA indicates 25 % weight loss at 205 degrees C from which the decomposition pattern is formulated. The DSC study indicates that the crystal undergoes only first order phase transitions. The FTIR spectrum indicates among others the presence of metal-nitrogen and metal-sulphur bonds thus confirming the formation of the complex. The second harmonic-generation (SHG) was confirmed by the emission of green radiation using Nd: YAG laser. (C) 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.