Structural, spectral, linear and nonlinear optical properties of new nonlinear optical l-histidinium trichloroacetate crystals

Single crystals of a new histidinium salt: l-histidinium trichloroacetate {abbreviated as LHTCA; [(C3N2H4)CH2CH(NH3)(CO2)]+CCl3COO−} were grown by slow evaporation of an aqueous solution at room temperature. The compound crystallizes in a non-centrosymmetric space group P21 of monoclinic system with cell parameters a = 5.4505(18) Å, b = 25.769(8) Å, c = 9.210 (2) Å and β = 99.98(2)°. The vibrational structure of the compound confirms the presence of various functional groups in the molecule. The UV-vis-NIR spectrum shows a good transparency in the whole of the region from ultraviolet to near IR. The Kurtz powder SHG measurement confirms the frequency doubling of the crystal. Thermal behaviour of the crystals has been investigated by DSC analysis. These preliminary results suggest that LHTCA crystal can act as a potential and promising candidate for frequency doubling applications even from the near UV region to the near IR.