Electronic excitations in epicocconone analogues: TDDFT methodological assessment guided by experiment

Area of Science:

• Computational Chemistry
• Spectroscopy
• Organic Chemistry

Background:

• Epicocconone derivatives are novel organic chromophores with potential applications.
• Accurate prediction of their UV/vis absorption spectra is crucial for understanding their properties.

Purpose of the Study:

• To develop and validate a reliable computational protocol for predicting UV/vis absorption spectra of epicocconone derivatives.
• To assess the influence of theoretical parameters on spectral prediction accuracy.

Main Methods:

• Time-dependent density functional theory (TDDFT) calculations.
• Systematic evaluation of density functionals, basis sets, and solvation models.
• Theory-experiment matching for protocol validation.

Main Results:

• Global hybrid functionals were inadequate for spectral description.
• Range-separated hybrids provided accurate results for all epicocconone derivatives.
• Double-ζ basis sets and polarizable continuum models were sufficient and necessary, respectively.
• Conformational consistency enhanced theoretical model accuracy.

Conclusions:

• A validated TDDFT protocol using range-separated hybrids and continuum solvation can accurately predict UV/vis spectra of epicocconone analogues.
• This protocol aids in the screening and design of novel organic chromophores.