Nucleation kinetics, growth, solubility and dielectric studies of L-proline cadmium chloride monohydrate semi organic nonlinear optical single crystal

Experimental and density functional theory (DFT): a dual approach to study the various important properties of monohydrated l-proline cadmium chloride for nonlinear optical applications

In the current work we have applied the experimental and quantum chemical techniques to study the electro-optical and nonlinear optical properties of l-proline cadmium chloride monohydrate (LPCCM). Synthesis and good quality single crystals of LPCCM were grown (size=20mm×12mm×10mm). Crystal structure was confirmed by powder X-ray diffraction study. The calculated FT-IR and FT-Raman frequencies were analyzed. Detailed optical studies were carried out and various optical parameters are calculated. Using density functional theory, molecular geometry of LPCCM was optimized within framework of B3LYP/6-31G(∗). The calculated HOMO-LUMO energy gap of 5.484eV and transition energy of 5.565eV has been found in semi-quantitative agreement with experimental results. The value of dipole moment and first hyperpolarizability of LPCCM are found to be 2 and 6 times respectively, higher than that of urea. The obtained results reveal that the titled compound is a good candidate for nonlinear applications having an excellent transparency trade-off value.

Synthesis and nucleation studies onL-leucine hydrobromide: a promising nonlinear optical material

To achieve good quality bulk size crystal growth, an assessment of the nucleation kinetics of a semi-organic L-leucine hydrobromide (L-LHBr) crystal was carried out using double-distilled water as solvent medium. The effect on metastable zone width (MSZW) with increasing temperature and on induction period with varied supersaturation level was determined experimentally and was found to be very well in accordance with the nucleation theory prospects. Thereafter, various other nucleation parameters, such as Gibbs free energy and interfacial energy, were also determined. The knowledge of these nucleation parameters indicated the requisite temperature domain and the appropriate growth technique, leading to the successful single-crystal growth of L-LHBr by slow cooling in the temperature range 298–291 K. The cooling rate of 0.25 K per day was optimized after repeated trials. X-ray diffraction and Raman analysis were performed on grown crystals for the verification of the material. High-resolution X-ray diffraction analysis was used to assess the crystalline perfection of the grown crystals. To further explore the properties of the grown crystals, photoluminescence and time decay studies, etching analysis, andZ-scan measurements were performed.

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.

Crystal growth and comparative studies of XRD, spectral studies on new NLO crystals: L-Valine and L-valinium succinate

Nonlinear optical single crystals of L-valine and L-valinium succinate were grown by slow evaporation solution growth method using water as the solvent. Purity of crystals was increased by the method of recrystallization. The grown crystals were analyzed by the single crystals X-ray diffraction pattern which proved that LVS belongs to orthorhombic crystals system. The presence of functional groups and modes of vibrations were identified by FT-IR spectroscopy. The chemical structure of crystals was established by FT-NMR technique. The transmission range of grown crystals was identified by UV-vis-NIR. The transmission region of LVS was more effective than LV which could be used for NLO applications. The nonlinear optical property of the grown crystals was confirmed by second harmonic generation test which shows the suitability of NLO applications.