Vibrational, electronic absorption, thermal and mechanical analyses of organic nonlinear optical material guanidinium phthalate

The FTIR and UV spectroscopic analysis have been carried out on guanidinium phthalate (GUP) crystal, an organic nonlinear optical material. The spectra are interpreted with the aid of normal coordinate analysis following structure optimizations and force field calculations based on density functional theory (DFT). The thermogravimetric (TG) and differential thermal analysis (DTA) ensures the thermal stability of the compound. Vickers microhardness values reveals the mechanical strength of the crystal.