Optical, spectral and dielectric studies of l-histidine added potassium hydrogen phthalate crystals

Optically transparent pure and amino acid added potassium hydrogen phthalate (KHP) single crystals were grown by slow evaporation technique at 32 °C. The entry of amino acid in the parent compound was confirmed by powder X-ray diffraction by the change in lattice parameters and also from the presence of amino group in the FT-IR and FT-Raman spectra in the case of amino acid added KHP crystals. The thermal and mechanical stability of the crystal was increased by the addition of amino acid. The optical studies revealed that the crystals have high transmittance in the entire visible region. The PL yield was also high for the crystals at 523 nm when excited with 480 nm. The SHG measurement confirms the emission of green light and the addition of amino acid has increased the SHG efficiency of the crystal. The crystals were also subjected to the dielectric study by varying the temperature and frequency.