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Ganapayya B.,SDM College Ujire | Jayarama A.,Mangalore Institute of Technology and Engineering MITE | Dharmaprakash S.M.,Mangalore University
Molecular Crystals and Liquid Crystals | Year: 2013

New nonlinear chalcone derivative: 3-(2,3-dichlorophenyl)-1-(pyridin-2-yl) prop-2-en-1-one (DCPP), has been synthesized and crystallized using dimethylformamide as solvent. The lattice parameters for the grown crystals were determined by using single crystal x-ray diffraction analysis; the DCPP crystallizes in the monoclinic system with P21 space group. The unit cell parameters of the crystal are: a = 7.4229(2) Å, b = 3.9889(1) Å, c = 21.2685(6) Å, β = 98.212(2), and V = 623.29(3)Å3. DCPP crystals were characterized by thermal and FTIR and UV-Vis spectral techniques. DCPP crystals are thermally stable up to 146.9°C. The UV absorption cut off wavelength is observed at 350 nm. DCPP crystals generate second harmonics of Nd:YAG laser operating at 1064 nm wavelength. The second harmonic generation (SHG) efficiency of the powdered DCPP sample was measured using Kurtz and Perry technique. The SHG efficiency is found to be equal to that of urea. © 2013 Copyright Taylor and Francis Group, LLC. Source


Menezes A.P.,Mangalore Institute of Technology and Engineering MITE | Jayarama A.,Sadguru Swami Nithyananda Institute of Technology SSNIT
Journal of Molecular Structure | Year: 2014

High quality single crystals of an efficient novel nonlinear optical (NLO) chalcone derivative 3-(4-nitrophenyl)-1-(pyridine-3-yl) prop-2-en-1-one (4NP3AP) that are transparent in the entire visible and infrared region are grown by the slow evaporation solution growth method at ambient temperature. The single crystal XRD studies reveal that the crystal belongs to monoclinic system with the noncentrosymmetric space group P21. The presence of functional groups in the compound is confirmed by different spectroscopic techniques. The surface morphology of the crystal is studied by scanning electron microscopy. The second harmonic generation (SHG) efficiency of 4NP3AP determined by Perry and Kurtz method is 56% that of potassium dihydrogen phosphate (KDP) single crystals. The static and frequency dependent molecular hyperpolarizabilities were computed using MOPAC 2012. Thermal analysis confirms that the crystal is thermally stable up to 177 °C. The origin of nonlinearity and the role of charge transfer direction on the nonlinearity of the chalcone have been discussed in detail. © 2014 Elsevier B.V. All rights reserved. Source


Prabhu A.N.,Manipal University India | Jayarama A.,Mangalore Institute of Technology and Engineering MITE | Subrahmanya Bhat K.,Manipal University India | Upadhyaya V.,Manipal University India
Journal of Molecular Structure | Year: 2013

A new potentially useful nonlinear optical (NLO) organic material, 1-(5-bromothiophen-2-yl)-3-(4-nitrophenyl)prop-2-en-1-one (BTNP), has been synthesized and grown as a high-quality single crystal by the slow evaporation technique. The grown crystals were chemically characterized by FT-IR and NMR studies. The grown crystal has been subjected to single-crystal X-ray diffraction studies and cell parameters of the crystal were determined. The title compound crystallizes in triclinic system with a noncentrosymmetric space group P1, with unit cell parameters a = 4.8093(4) Å, b = 5.9428(6) Å, c = 11.5153(11) Å, α = 94.999(4), β = 95.780(3), γ = 96.396(4) and V = 323.79(5) Å3. The thermal stability of the crystal was determined from DSC curve. The grown crystals were characterized for their optical transmission and mechanical hardness. The second harmonic generation (SHG) efficiency of the crystals was obtained by powder technique using Nd:YAG laser and is found to be four times that of urea. © 2012 Elsevier B.V. All rights reserved. Source


Menezes A.P.,Mangalore Institute of Technology and Engineering MITE | Ng S.W.,University of Malaya
Journal of Molecular Structure | Year: 2015

An efficient nonlinear optical material 2E-3-(4-bromophenyl)-1-(pyridin-3-yl) prop-2-en-1-one (BPP) was synthesized and single crystals were grown using slow evaporation solution growth technique at room temperature. Grown crystal had prismatic morphology and its structure was confirmed by various spectroscopic studies, elemental analysis, and single crystal X-ray diffraction (XRD) technique. The single crystal XRD of the crystal showed that BPP crystallizes in monoclinic system with noncentrosymmetric space group P21 and the cell parameters are a = 5.6428(7) Å, b = 3.8637(6) Å, c = 26.411(2) Å, β = 97.568(11) deg and v = 575.82(12) Å3. The UV-Visible spectrum reveals that the crystal is optically transparent and has high optical energy band gap of 3.1 eV. The powder second harmonic generation efficiency (SHG) of BPP is 6.8 times that of KDP. From thermal analysis it is found that the crystal melts at 139 °C and decomposes at 264°C. High optical transparency down to blue region, higher powder SHG efficiency and better thermal stability than that of urea makes this chalcone derivative a promising candidate for SHG applications. Furthermore, effect of molecular planarity on SHG efficiency and role of pyridine ring adjacent to carbonyl group in forming noncentrosymmetric crystal systems of chalcone family is also discussed. © 2015 Elsevier B.V. All rights reserved. Source


Prabhu A.N.,Manipal University India | Upadhyaya V.,Manipal University India | Jayarama A.,Mangalore Institute of Technology and Engineering MITE | Subrahmanya Bhat K.,Manipal University India
Materials Chemistry and Physics | Year: 2013

A new potentially useful nonlinear optical organic material, 1-(5-chlorothiophen-2-yl)-3-(2,3-dimethoxyphenyl)prop-2-en-1-one, has been synthesized and grown as a high-quality single crystal by the slow evaporation technique. The grown crystals were characterized by FT-IR, NMR, thermal analysis, and UV-visible spectroscopy. The material is thermally stabile up to 111 °C. The mechanical property of the grown crystals was studied using Vickers microhardness tester and the load dependence hardness was observed. The third order nonlinear optical properties of the material such as real and imaginary part of χ(3), nonlinear absorption coefficient and nonlinear refractive index were determined using nanosecond laser pulses at 532 nm wavelength by employing Z-scan technique. The nonlinear refractive index is found to be of the order of 10-11 cm2 W-1. The magnitude of third order susceptibility is of the order of 10-13 esu. The observed increase in the third order nonlinearity in these molecules clearly indicates the electronic origin. The compounds exhibit good optical limiting at 532 nm. The best optical limiting behavior of this molecule is due to the substituted strong electron donor. © 2012 Elsevier B.V. All rights reserved. Source

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