Growth and characterization of a new metal-organic nonlinear optical bis (thiourea) cadmium zinc chloride single crystals

Growth and characterization of Melaminium bis (trichloroacetate) dihydrate

Single crystals of melaminium bis (trichloroacetate) dihydrate have been grown successfully by slow evaporation solution growth technique at room temperature. Single crystal X-ray diffraction analysis reveals that the compound crystallizes in monoclinic system with non -centrosymmetric space group C2 with lattice parameters a=17.70 Å, b=8.44 Å, c=6.09 Å, α=90°, β=100.24°, γ=90° and V=900 (Å)3. The UV-Vis transmittance spectrum shows that the crystal has a good optical transmittance in the entire visible region with lower cutoff wavelength of 351 nm. The vibrational frequencies of various functional groups present in the crystal have been derived from FI-IR, FT-Raman and Confocal Raman analyses. The chemical structure of the compound was established by 1H and 13C NMR spectrum. TGA-DTA analysis reveals that the materials have good thermal stability and the melting point of the crystal is found to be 195°C. The dielectric response of the crystals was studied in the frequency range 50 Hz to 5 MHz at different temperatures and the results are discussed. Etching studies show the growth pattern of the crystals. The second harmonic generation efficiency was measured in comparison with KDP by employing powder Kurtz method.

Growth and spectroscopic investigation of a new crystal for NLO applications: C₁₀H₂ ₀KN₅O₉

Nonlinear optical crystals of Bis (l-glutamine) potassium nitrate (BGPN) were grown by slow evaporation technique at ambient temperature. Solubility and metastable zone width of BGPN in aqueous solution were determined. The grown crystal was characterized by single crystal XRD, Powder XRD, FT-IR (1)H NMR, EDAX, mass and optical spectroscopic techniques. Single crystal XRD revealed that compound crystallizes in orthorhombic system with non-centrosymmetric space group P2(1)2(1)2(1). The sharp peaks from powder XRD spectrum show the high crystallinity of the grown crystal. FT-IR confirms the presence of functional groups and molecular structure was confirmed by (1)H NMR spectrum of the grown crystal. Molecular mass of BGPN sample has been verified by high resolution mass spectroscopic analysis. The presence of potassium in the compound and composition of grown crystals was confirmed on the basis of energy dispersive analysis of X-ray (EDAX). Thermal stability of the grown crystal was studied by TGA-DTA analysis. An optical UV-Vis-NIR spectrum for BGPN sample was recorded in the range of 190-1100 nm. Fluorescence studies shows material BGPN emits blue fluorescence. Second harmonic generation (SHG) studies have been performed by famous Kurtz powder technique with reference to standard potassium dihydrogen phosphate single crystals (KDP). It is found from this technique that SHG efficiency of BGPN is in comparison to that of standard KDP crystals.