Physical‐organic aspects along with linear and nonlinear optical properties of benzene sulfonamide compounds: In silico analysis

The sulfonamides class of drugs is known due to superb biological and notable nonlinear optical (NLO) applications. The current study reports detailed computational and spectroscopic studies of 16 novel benzene sulfonamides compounds. Computational studies on these compounds (1–16) have been performed with the aid of density functional theory (DFT) at B3LYP/6‐31G (d,p) basis set. B3LYP with the conjunction of 6‐31G(d,p) has been used to gain optimized geometries of these compounds. Different key parameters have been performed to analyze the structural‐property relationship, stability, reactivity, charge transferability, and NLO response of these novel compounds. Electronic properties including frontier molecular orbitals (FMOs) alignment, natural bond orbital (NBO) analysis, spectroscopic fourier‐transform infrared spectroscopy (FT‐IR), and NLO properties were calculated using B3LYP/6‐31G(d,p) and M06‐2X/6‐31G(d,p) basis sets. Natural bonding orbital analysis confirmed the successful electron transferability between donor moiety and acceptor moiety. The molecular electrostatic potential analysis unveils the intramolecular hydrogen bonding along with different reactive sites in these compounds 1–16. Global indices of reactivity were analyzed using energies of frontier molecular orbitals of compounds 1–16, which suggested that these compounds are chemically hard and stable compounds. Absorption maxima of all compounds were estimated with aid of time‐dependent DFT at B3LYP/6‐31G(d,p) basis set which disclosed the best agreement between experimental and DFT‐based recorded spectra. FT‐IR analysis (at B3LYP/6‐31G(d,p)) confirmed different modes of vibration in all the title compounds and also exhibit a concrete relation with experimentally recorded IR spectrums. Moreover, all the compounds (1–16) show good NLO response. NLO responses of 1–16 compounds were computed at the same level of B3LYP/6‐31G (d,p), which is found to be greater than the standard molecule. All these analyses suggest that 1–16 benzene sulfonamides compounds are found to be suitable candidates for biological and NLO applications.