Unlocking inverted singlet-triplet gap in alternant hydrocarbons with heteroatoms.

ABSTRACT: Fifth-generation organic light-emitting diodes exhibit delayed fluorescence enabled by exothermic reverse intersystem crossing due to a negative singlet-triplet gap, where the first excited singlet lies below the triplet. This phenomenon, termed delayed fluorescence from inverted singlet and triplet states (DFIST), has been experimentally confirmed only in two triangular molecules with a central nitrogen atom. Here, we report a high-throughput virtual screening of 30 797 BN-substituted polycyclic aromatic hydrocarbons (BNPAH) derived from 77 parent scaffolds with 2-6 rings. Using a multi-level workflow that combines structural stability criteria with accurate excited-state calculations, we identify the top 46 DFIST-BNPAH candidates with singlet-triplet gaps less than -0.015 eV. Notably, th

SUBMITTER: Majumdar A 

PROVIDER: S-EPMC12257002 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature