Accuracy of One-Electron Technique for Estimating LUMO Energies of Triphenylamine Derivatives

Accurate estimations of HOMO, LUMO, and HOMO-LUMO energy gaps of organic small molecules (OSMs) are critical to understand experimental observations and assist in rational design of new OSMs in many OSM-based technologies. Recently, a one-electron technique was used to estimate LUMO energies of cyclopenta-fused polycyclic aromatic hydrocarbons and found the technique improves the accuracy of predictions of LUMO and HOMO-LUMO gap. In this work, we evaluated the accuracy of this technique in predicting the LUMO and HOMO-LUMO energy gaps of 4-vinyl-N,N-di(p-tolyl)aniline (MTPA) and its six derivatives from ten functionals: B3LYP, B3PW91, HSEH1PBE, MPW91PW91, CAM-B3LYP, wB97XD, BPV86, PBE, TPSS, and HCTC. This study shows that the accuracies of predictions using the one-electron technique are improved significantly for the results from wB97XD and CAM-B3LYP functionals, while the accuracy of predictions does not improve much for the results from B3LYP, B3PW91, and MOPW1PW91. The accuracy of predictions from BPV86, PBE, TPSS, and HCTC decreases upon using the one-electron technique.