Unique optical properties of Eu3+ doped l-histidine hydrochloride mono hydrate single crystals from low temperature growth technique

A low-temperature solution method was utilized to grow single crystals of Eu³⁺doped l-histidine hydrochloride monohydrate. The quality of the crystals was confirmed by high-resolution X-ray diffraction measurements with full width at half maximum (FWHM) of rocking curve at 8arc per sec. The incorporation of Eu³⁺ ions into the lattice was confirmed by functional group analysis using Fourier Transform Infrared (FTIR) spectroscopy. The amount of Eu³⁺ ions was found to be 0.08 weight (%) using energy dispersive X-ray analysis. The crystal's thermal and mechanical properties were tested as well. The unique spectral properties such as UV-Vis transmittance, nonlinear optical efficiency (NLO), photoluminescence (PL) and its lifetime were measured. The PL study revealed that the intensity of ⁵D₀→⁷F₂ emission of Eu³⁺ is stronger than that of ⁵D₀→⁷F₁ emission and the decay measurement showed a life time of 7.2410μs. The photoluminescence results prove that l-histidine hydrochloride monohydrate is a new, highly efficient host material for europium ion red emissions.

Studies on influence of Cd(2+) ions in unidirectional growth and characterization of l-Cysteine hydrochloride monohydrate single crystals

Cadmium doped l-Cysteine hydrochloride monohydrate (Cd(2+)-C3H7NO2S⋅HCl⋅H2O), a non-linear optical crystal, was grown by conventional as well as unidirectional solution growth techniques. While the dimension of the conventionally grown crystal was 16×14×5mm(3), the dimension of the crystal grown unidirectional method was 32mm long and 6mm diameter. The grown crystals were studied using XRD for phase analysis, HRXRD for crystalline perfection and UV-Vis NIR spectroscopy for optical properties. The high crystalline perfection was found in the crystal grown by unidirectional method than that grown by conventional one. FTIR study indicates that Cd(2+) ion was coordinated to l-Cysteine⋅HCl⋅H2O through S ligand. The nonlinear optical character of the title compound was observed by measuring the SHG efficiency, which is 1.35times to that of KDP by Kurtz technique.