Experimental and theoretical investigation of a novel dihydropyridine derivative: synthesis, photophysical characterization, and enhanced nonlinear optical properties in solvent media

Abstract

In this study, we synthesized and characterized a novel dihydropyridine derivative, 4-(5-(4-(dimethylamino)phenoxy)thiophene-2-yl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate employing 1H-NMR, DEPT-135, 2D NMR, LCMS and FT-IR techniques. The compound's photophysical properties were examined through UV-vis absorption, emission spectra, fluorescence lifetime in five different solvents. Additionally, we investigated the impact of viscosity on these properties in a glycerol-methanol solution. Complementing the experimental studies, DFT-based theoretical computations at the PCM/DFT/M11/6-311++G(d,p) level were used to explore the electronic and nonlinear optical properties. A strong correlation of the experimental absorption and emission spectral data with the theoretical predictions validates the computational approach. The nonlinear optical parameters were calculated using an optimally tuned range-separated hybrid functional, where the range-separation parameter was self-consistently adjusted to ensure accurate predictions of electronic and optical properties. Key findings include the total dipole moment and static and dynamic parameters such as linear polarizability, Hyper-Rayleigh scattering first hyperpolarizability, and second hyperpolarizabilities. Notably, the compound exhibited significant second-order nonlinear optical properties at 1064 nm, suggesting potential applications in NLO materials. Moreover, the values obtained are much higher than those reported for some organic compounds. These results support the potential of this derivative for future optical applications.