Color Characterization of Dispersed Dyes Based on Quantum Chemistry Calculations

The UV–visible absorption spectra of disperse dyes are intrinsically dependent on their chemical structure, a critical determinant of the dyes’ color performance. An investigation into the correlation between molecular structure and color in disperse dyes was undertaken, grounded in the principles of quantum chemistry pertaining to material light absorption. Quantum chemistry computational tools and auxiliary software were employed to delineate the correlation between the structure and color properties of monoazo orange disperse dyes. Initial molecular conformations of three disperse dye molecules were generated via Confab and subsequently optimized utilizing the GFN2‐xTB framework. The quantum chemical density functional theory framework was employed to compute and refine the lowest energy conformations alongside thermal free energy corrections. Single‐point energies of each conformation at 298.15 K were ascertained employing the M06‐2X/def2‐TZVPP approach, with those conformations possessing a Boltzmann distribution ratio of at least 5% selected for subsequent excited‐state calculations via diverse functionals. Comparative analysis of these computational data