Quantum Theory Project (QTP) functionals, which are based on Correlated Orbital Theory (COT) conditions, are compared to popular exchange-correlation (XC) functionals (B3LYP, PBE0, CAM-B3LYP, ωB97XD, and HSE06) for describing fundamental quantities of conducting polymers (PEDOT, polyfuran, and polythiophene). Thus, ωB97XD yields the best results for ionization potentials, with discrepancies ranging from −0.08 to 0.34 eV across polymers compared to reference data. However, QTP functionals are superior for electron affinities, with deviations between −0.10 and 0.26 eV for polyfuran and polythiophene. Consequently, ωB97XD and QTP functionals also provide the most accurate fundamental gap predictions, especially by CAM-QTP-00 and ωB97XD, with deviations from −0.47 to 0.85 eV for the same two polymers. Additionally, LC-QTP is the most successful XC functional for the lowest lying singlet to triplet excitation energies, with deviations between −0.52 and −0.27 eV. Hence, this study reinforces the promising performance of COT-based XC functionals for materials science applications.
Bartaquim et al. (Sat,) studied this question.