Investigations on the physicochemical properties of 2,4-dinitrophenol: Efficient organic nonlinear optical crystal for frequency doubling

Good quality single crystal of 2,4-dinitrophenol is grown by slow evaporation solution growth technique. The cell parameters are determined from the single crystal X-ray analysis. The characteristic frequencies of the various functional groups are identified by investigating FTIR and FT Raman spectra and they are assigned. The result of thermal analysis reveals the decomposition mechanism and the thermal stability of the compound. Optical transparency in the visible region, the lower cut-off wavelength and the band gap energy are estimated from the optical studies. The first order static hyperpolarizability value is calculated and it is 8.4 times greater than that of the urea. The gap between highest occupied molecular orbital and the lowest unoccupied molecular orbital is calculated, which is useful for estimating the efficiency of second harmonic generation. The crystal exhibits high relative conversion efficiency when compared to urea.