S. Selvasekarapandian et al., VIBRATIONAL STUDIES OF BIS(THIOUREA) CADMIUM CHLORIDE AND TRIS(THIOUREA) ZINC-SULFATE SEMIORGANIC NONLINEAR-OPTICAL CRYSTALS, Crystal research and technology, 32(2), 1997, pp. 299-309
Single crystals of Bis(thiourea) cadmium chloride (BTCC), and Tris(thi
ourea) zinc sulphate (TZnS) have been grown from saturated aqueous sol
ution by slow evaporation method at room temperature. The laser Raman
and FT-IR spectra on these crystals are recorded in the frequency rang
e 50-4000 cm(-1). The spectral data of BTCC and TZnS are interpreted o
n the basis of thiourea crystal vibrational data. The vibrational freq
uencies in the FT-IR and Raman spectra of BTCC and TZnS establish that
ZnSO4 and CdCl2 metal complex are coordinated with thiourea by the me
tal to sulfur bonds. The effect of the metal complexation on thiourea
molecule and nature of bands due to different vibrational modes have b
een discussed. The lattice vibrational frequencies changes have also b
een observed and analyzed.