Experimental and theoretical investigations on N,N′-diphenylguanidinium dihydrogen phosphite – A semi-organic nonlinear optical material

Abstract

Single crystal of N,N′-diphenylguanidinium dihydrogen phosphite (DPGP) was grown by a slow evaporation technique and was characterized by single crystal X-ray diffraction and powder X-ray diffraction to confirm the structure and crystalline nature of DPGP crystal. UV–vis spectral study revealed that the DPGP crystal is optically transparent. The chemical bonding and presence of various functional groups were confirmed by the FT-IR and FT-Raman spectral studies. The thermal behavior of DPGP crystal was analyzed by simultaneous TG-DTA studies. The laser induced surface damage threshold study was carried out for the grown crystal using Nd:YAG laser. The second harmonic generation (SHG) nonlinearity of the grown crystalline sample was measured by the Kurtz and Perry powder technique. The quantum chemical analyses were performed by density functional theory (DFT) using B3LYP/6-31G (d,p) basis set.