G. Anandha Babu

Growth and characterization of 2-amino-4-picolinium toluene sulfonate single crystal

2-Amino-4-picolinium toluene sulfonate (2A4PTS), a new organic material, was synthesized and grown as single crystals in room temperature by slow evaporation solution growth technique using water as solvent. The crystal structure of 2A4PTS has been determined using single crystal X-ray diffraction studies. 2A4PTS belongs to monoclinic crystal system. The molecular arrangements in the crystal were studied. The structural perfection of the grown crystals has been analysed by high-resolution X-ray diffraction (HRXRD) rocking curve measurements. Fourier transform infrared (FTIR) spectral studies have been performed to identify the functional groups. The optical transmittance window and the lower cutoff wavelength of the 2A4PTS have been identified by UV-Vis-NIR studies. The nonlinear optical properties have been investigated by Z-scan method. The nonlinear refractive index and linear absorption coefficient of the 2A4PTS are found to be in the order of 10(-8) cm(2)/W and 10(-4) cm/W, respectively. The laser induced surface damage threshold for the grown crystal was measured using Nd:YAG laser. Thermal analysis carried out on the compound reveals that 2A4PTS is stable up to 133°C. The microhardness test was carried out and the load dependent hardness was measured.

Synthesis, growth and spectroscopic investigation of an organic molecular charge transfer crystal: 8-hydroxy quinolinium 4-nitrobenzoate 4-nitrobenzoic acid.

An organic intermolecular charge transfer complex salt of 8-Hydroxy quinolinium 4-nitrobenzoate 4-nitrobenzoic acid (OPNB) has been synthesized. Single crystals of OPNB were grown by slow solvent evaporation solution growth technique at room temperature. The (1)H and (13)C NMR spectra were recorded to confirm the molecular structure of the complex salt. The crystal structure of OPNB has been determined by single crystal XRD analysis and it belongs to triclinic crystal system with space group P-1. Fourier transform infrared (FT-IR) spectral study has been carried out to identify the various functional groups present. The UV-Vis-NIR transmittance spectrum was recorded in the range 200-2500nm, to find the suitability of the single crystal for various optical applications. The thermal stability of the crystal was investigated using thermogravimetric (TG) and differential thermal analyses (DTA).

Synthesis, growth, spectral, and thermal studies of a new organic molecular charge transfer complex crystal: 3-Nitroaniline 4-methyl benzene sulfonate

A new organic intermolecular charge transfer complex 3-nitroaniline 4-methyl benzene sulfonate (NATS) has been successfully synthesized and good optical quality single crystals grown by slow solvent evaporation solution growth technique at room temperature using methanol as the solvent. The (1)H and (13)C NMR spectra were recorded to establish the molecular structure of the title complex. The crystal structure of NATS has been determined by single crystal XRD analysis and it belongs to orthorhombic crystal system with space group Pbca. Fourier transform infrared (FT-IR) spectral study has been carried out to confirm the presence of various functional groups present in the complex. Electronic absorption spectrum was recorded to find the prevalent charge transfer activity in the complex. The UV-Vis-NIR transmission spectrum was recorded in the range 200-2500 nm, to find the optical transmittance window and lower cut off wavelength of the title crystal. The thermal stability of the title complex crystal was studied by using thermo-gravimetric and differential thermal analyses and found that the compound is stable up to 215 °C.

Synthesis, growth, structure and spectroscopic characterization of a new organic nonlinear optical hydrogen bonding complex crystal: 3-carboxyl anilinium p-toluene sulfonate.

A new organic nonlinear optical hydrogen bonding complex salt of 3-carboxyl anilinium p-toluene sulfonate has been synthesized and highly transparent good quality single crystals of it were successfully grown employing slow solvent evaporation solution growth technique at ambient temperature. The (1)H and (13)C NMR spectra were recorded to establish the molecular structure. The single crystal XRD analysis carried out reveals that the title salt crystallizes in monoclinic crystal system with non-centrosymmetric P2₁ space group. The FT-IR spectrum was recorded to confirm the presence of various functional groups in the grown title crystal. The UV-Vis-NIR transmission spectrum was recorded to apprehend the suitability of the single crystal of the title salt for various optical and NLO applications. The TG/DTA thermal analysis was performed to establish the thermal stability of the crystal. The SHG activity in the grown crystal was identified employing the modified Kurtz-Perry powder test. The electronic charge distribution and reactivity of the molecules within the title complex was studied by HOMO and LUMO analysis and the molecular electrostatic potential (MEP) of the title crystal was performed using the B3LYP method.

Growth and characterization of 4-chloro-3-nitrobenzophenone single crystals using vertical Bridgman technique

4-chloro-3-nitrobenzophenone (4C3N) has been grown by using vertical Bridgman technique. The grown crystal was confirmed by Powder X-ray diffraction analysis. The crystalline perfection of the grown crystal was examined by high-resolution X-ray diffraction study. The fluorescence spectra of grown 4C3N single crystals exhibit emission peak at 575 nm. The micro hardness measurements were used to analyze the mechanical property of the grown crystal.

Studies on the growth and characterization of an organic single crystal – 1,3,5- Triphenylbenzene

Abstract Single crystals of a pure hydrocarbon, 1,3,5-Triphenylbenzene (TPB) have been successfully grown using toluene as a solvent by controlled slow cooling solution growth technique. TPB crystallises in orthorhombic structure with the space group Pna21. High-resolution X-ray diffraction measurements were carried out to find the structural perfection of the grown TPB crystal. The functional groups of the grown crystal were identified using FTIR measurements. The range and percentage of the optical transmission are ascertained by recording the UV–Vis spectrum. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were carried out to study its thermal properties. The initial screening of NLO properties of TPB crystal is identified using powder second-harmonic generation studies. Dielectric studies have been carried out on the grown crystals. The mechanical stability of TPB was studied from Vickers microhardness test. Laser damage threshold value was determined using Nd:YAG laser operating at 1064 nm.

Growth, structural, optical, thermal and laser damage threshold studies of an organic single crystal: 1,3,5 – triphenylbenzene (TPB)

Good quality single crystals of pure hydrocarbon 1,3,5-Triphenylbenzene (TPB) have been successfully grown using toluene as a solvent using controlled slow cooling solution growth technique. TPB crystallizes in orthorhombic structure with the space group Pna21. The structural perfection of the grown crystal has been analysed by high resolution X-ray diffraction measurements. The range and percentage of the optical transmission are ascertained by recording the UV-vis spectrum. Thermo gravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study its thermal properties. Powder second harmonic generation studies were carried out to explore its NLO properties. Laser damage threshold value has been determined using Nd:YAG laser operating at 1064 nm.

Growth improvement and characterization of AgGaSe2 chalcopyrite single crystals using Bridgman technique

High pure, single phase, free of voids and crack-free AgGaSe2 single crystals have been grown by vertical Bridgman technique with steady ampoule rotation. Powder X-ray diffraction, High-resolution X-ray diffraction, Micro-Raman scattering and Optical studies have been performed and the results are discussed in detail.