Vibrational Studies of Bis(thiourea) Cadmium Chloride and Tris(thiourea) Zinc Sulphate Semiorganic Non‐linear Optical Crystals

Abstract

Single crystals of Bis(thiourea) cadmium chloride (BTCC), and Tris(thiourea) zinc sulphate (TZnS) have been grown from saturated aqueous solution by slow evaporation method at room temperature. The laser b a n and FT-IR spectra on these crystals are recorded in the frequency range 50-4000cm-'. The spectral data of BTCC and TZnS are interpreted on the basis of thiourea crystal vibrational data. The vibrational frequencies in the FT-IFt &d Raman spectra of BTCC and TZnS establish that ZnSOr and CdClz metal complex are coordinated with thiourea by the metal to sulfur bonds. The effect of the metal complexation on thiourea molecule and nature of bands due to different vibrational modes have been discussed. The lattice vibrational frequencies changes have also been observed and analyzed.

Growth, Structural, Spectral and Optical Studies on Pure and L-Alanine Mixed Bisthiourea Cadmium Bromide (LABTCB) Crystals

“…Also the CS stretching bands of thiourea (1417 and 740 cm -1 ) are shifted to lower frequencies in BTCB and LABTCB. These results reveal that the metals coordinate with thiourea through sulphur [12]. The slight variation in the observed frequencies of BTCB and LABTCB are due to the presence of L-alanine.…”

HUMO-LUMO Studies on Methyl Orange Doped ZTS Crystals for Laser Applications

“…Many organic molecules that contain conjugated π electrons are characterized hyperpolarizabilities and are analyzed by means of vibrational spectroscopy [14]. In most cases, even in the absence of inversion symmetry, the strongest bands in the Raman spectrum are weak in the IR spectrum and vice versa.…”

The Effect of Phosphate Mixing on Structural, Spectroscopic, Mechanical and Optical Properties of Zinc tris Thiourea Sulphate (ZTS) Single Crystals

“…Each of the nitrogen atoms in thiourea is connected to two hydrogen atoms. Zinc ion is tetrahedraly coordinated to three sulphur atoms of thiourea and to an oxygen atom of sulphate ion [8]. The FTIR spectra of pure ZTS and 10 and 25 mol % of phosphate mixed ZTS were recorded in the range 450-4000 cm -1 and they are shown in Fig.…”

“…1(a-c). The spectra of ZTS and phosphate mixed ZTS crystals can be interpreted as follows: The N-H absorption frequency in the region between 3000 cm -1 and 4000 cm -1 arises due to symmetric and asymmetric vibration of NH 2 group of the zinc coordinated thiourea [8]. The bending vibration of NH 2 was observed around 1627 cm -1 [9].…”

“…The bending vibration of NH 2 was observed around 1627 cm -1 [9]. The C-N and N-C-N stretching vibration are observed near 1114 cm -1 and 1510 cm -1 , respectively [8].…”