Synthesis, crystal structures, spectroscopy, and quantum chemical studies on the 4-dimethylaminopyridinium-2,4-dinitrophenolate: an organic NLO material for optoelectronics

ContextIn this work, the 4-dimethylaminopyridinium-2,4-dinitrophenolate (4DMAP + 2,4DNP) by slow evaporation solution growth method has been presented. The Fourier transform infrared (FT-IR) (4000-400 cm-1) and FT-Raman (4000-50 cm-1) spectra were recorded for the grown crystal.MethodsThe computational calculation has been carried out with density functional theory (DFT) in ground state with Gaussian program package. Optimized geometrical parameters (bond distances, bond angles, and dihedral angles) have been obtained and compared with X-ray crystallography data. The calculated fundamental vibrational frequencies from DFT/B3LYP with 6-311 + + G(d,p) level of theory were scaled so as to agree with the observed results, and the scaling factors were reported.ResultsExperimental and computed ultraviolet-visible (UV-Vis) spectra in acetone and methanol solvents were found comparable to each other. Furthermore, the frontier molecular orbitals (FMOs) energies, molecular electrostatic potential (MEP), nonlinear optical (NLO), hirshfeld surface (HS), and global chemical descriptors of the molecule were also calculated. The thermal stability and the melting point of the title compound were analyzed by the thermogravimetric analysis/differential thermal analysis (TGA/DTA) techniques. The mechanical behavior of the organic single crystal was measured by Vickers micro-hardness method. The third-order nonlinear optical properties such as nonlinear refractive index (n2), nonlinear absorption coefficient (beta), optical nonlinear susceptibility Re chi(3), and optical nonlinear susceptibility Im chi(3) were calculated by using the open and closed aperture Z-scan technique.ConclusionThe theoretical and experimental NLO values clearly proposed that the nonlinearity of 4DMAP + 2,4DNP molecule could be helped as a potential candidate for optical limiting, frequency doubling, and optical switching applications.

Automated summary

In this study, the 4-dimethylaminopyridinium-2,4-dinitrophenolate (4DMAP + 2,4DNP) was prepared using the slow evaporation solution growth method. The experimental and computational results showed that the 4DMAP + 2,4DNP molecule exhibits excellent nonlinear optical properties, making it a potential candidate for optical limiting, frequency doubling, and optical switching applications.