Abstract

A comprehensive quantum chemical investigation was carried out on 2-[(8-bromonaphtho[2,1-b]furan-2-yl)carbonyl]-N-(3-chlorophenyl)hydrazinecarbothioamide (A1) to evaluate its structural, electronic, and molecular reactivity characteristics. Density Functional Theory (DFT) calculations were performed using the B3LYP functional with the 6-31G(d,p) basis set in Gaussian 09. The optimized geometry was validated by frequency analysis, confirming the absence of imaginary vibrational modes. Frontier molecular orbital analysis demonstrated effective intramolecular π-electron delocalization, with the HOMO mainly localized over the donor region and the LUMO distributed across the acceptor fragment, indicating pronounced charge-transfer behavior. The calculated HOMO–LUMO energy gap of 4.2758 eV suggests favorable kinetic stability and moderate chemical reactivity. Molecular electrostatic potential mapping revealed electron-rich regions around the carbonyl oxygen and thiocarbonyl sulfur atoms, identifying the principal reactive sites of the molecule. Furthermore, quantum chemical descriptors confirmed its balanced electron-donating and electron-accepting ability. These findings establish A1 as a structurally stable donor–acceptor system with promising potential for optoelectronic, nonlinear optical, and molecular sensing applications.