Quantum Computing Analysis of Naphthalene Compound: Electronic Structure, Optical, and Thermochemical Approaches using DFT and HF

The novelty of the work lies in the application of quantum computing analysis, specifically employing density functional theory (DFT) and Hartree-Fock (HF) techniques with various basis sets (aug-cc-pVQZ, 3-21G, 6-31G, 6-311G, and SDD), this work examined the structure and characteristics of naphthalene. The theoretical nature of naphthalene’s structure and characteristics:  Highest Occupied Molecular Orbital (HOMO), Lowest Unoccupied Molecular Orbital (LUMO), band gap BG, density of state (DOS), Ultraviolet (UV), and Natural Bond Orbital (NBO) are explored. Several additional characteristics have been studied: thermochemical properties at standard temperature and pressure, and their optical properties (Optical BG with the indirect and direct transition).  The DFT/aug-cc-pVQZ basis was used with a fixed value of 4.75 eV to determine the HOMO-LUMO gap of naphthalene in this investigation. We find that the gaps of 4.71, 4.873, and 4.74 eV, respectively, in a recent density-functional theory (DFT) study that agrees with our results.