biostudies-literatureJorner KNatural Sciences and Engineering Research Council of CanadaCanada First Research Excellence FundSocial Sciences and Humanities Research Council of CanadaCanadian Institute for Advanced ResearchNatural Resources CanadaCanadian Institutes of Health ResearchVetenskapsr?det2445-2456https://www.ebi.ac.uk/biostudies/studies/S-EPMC10983003biostudies-literatureUnknown128(12)Molecules with an inverted energy gap between their first singlet and triplet excited states have promising applications in the next generation of organic light-emitting diode (OLED) materials. Unfortunately, such molecules are rare, and only a handful of examples are currently known. High-throughput virtual screening could assist in finding novel classes of these molecules, but current efforts are hampered by the high computational cost of the required quantum chemical methods. We present a method based on the semiempirical Pariser-Parr-Pople theory augmented by perturbation theory and show that it reproduces inverted gaps at a fraction of the cost of currently employed excited-state calculations. Our study paves the way for ultrahigh-throughput virtual screening and inverse design to accelerate the discovery and development of this new generation of OLED materials.The journal of physical chemistry. AUltrafast Computational Screening of Molecules with Inverted Singlet-Triplet Energy Gaps Using the Pariser-Parr-Pople Semiempirical Quantum Chemistry Method.PMC109830032020-00314Lavigne CAspuru-Guzik AJorner KPollice RfalseUltrafast Computational Screening of Molecules with Inverted Singlet-Triplet Energy Gaps Using the Pariser-Parr-Pople Semiempirical Quantum Chemistry Method.Molecules with an inverted energy gap between their first singlet and triplet excited states have promising applications in the next generation of organic light-emitting diode (OLED) materials. Unfortunately, such molecules are rare, and only a handful of examples are currently known. High-throughput virtual screening could assist in finding novel classes of these molecules, but current efforts are hampered by the high computational cost of the required quantum chemical methods. We present a method based on the semiempirical Pariser-Parr-Pople theory augmented by perturbation theory and show that it reproduces inverted gaps at a fraction of the cost of currently employed excited-state calculations. Our study paves the way for ultrahigh-throughput virtual screening and inverse design to accelerate the discovery and development of this new generation of OLED materials.2024-01-01T00:00:00Z2024 Mar2025-04-22T08:19:50.909Z2025-04-05T22:30:06.316ZS-EPMC109830033848544810.1021/acs.jpca.3c06357