Ultraviolet-visible spectra of pyrromethene 580 laser dye utilizing density functional theory: Examination of molecular structure, electronic characteristics

Abstract

This study presents a theoretical simulation of the pyrromethene 580 molecule using density functional theory (DFT) with the B3LYP functional and a 6-31G (d,p) basis set. DFT methods are employed to determine bond lengths and angles, as well as electronic properties, including electronic energy, dipole moment, electron affinity, ionization potential, chemical Potential, absolute hardness, perfect softness, and electrophilicity index (ω). Additionally, the molecular electrostatic potential and absorption spectra are analyzed. The computed energy value is -1192.534269 Hartree. The dipole moment is found to be 3.96 Debye, indicating a non-uniform charge distribution. The energy gap is calculated as 2.96 eV, reflecting the molecule’s stability, while the maximum absorption wavelength (λmax) is 515 nm.