{"paper":{"title":"Spontaneous exciton dissociation enables spin state interconversion in delayed fluorescence organic semiconductors","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cond-mat.mtrl-sci"],"primary_cat":"physics.app-ph","authors_text":"Alexander J. Gillett, Bluebell H. Drummond, Claire Tonnel\\'e, Darcy M. L. Unson, David Beljonne, David Casanova, Elena Zaborova, Emrys W. Evans, Fr\\'ed\\'eric Castet, Fr\\'ed\\'eric Fages, Gaetano Ricci, Giacomo Londi, Lin-Song Cui, Manon Catherin, Neil C. Greenham, Patrick J. Conaghan, Richard H. Friend, Weimin M. Chen, Yoann Olivier, Yuttapoom Puttisong","submitted_at":"2021-06-29T15:40:18Z","abstract_excerpt":"Engineering a low singlet-triplet energy gap ({\\Delta}EST) is necessary for efficient reverse intersystem crossing (rISC) in delayed fluorescence (DF) organic semiconductors, but results in a small radiative rate that limits performance in LEDs. Here, we study a model DF material, BF2, that exhibits a strong optical absorption (absorption coefficient =3.8x10^5 cm^-1) and a relatively large {\\Delta}EST of 0.2 eV. In isolated BF2 molecules, intramolecular rISC is slow (260 {\\mu}s), but in aggregated films, BF2 generates intermolecular CT (inter-CT) states on picosecond timescales. In contrast to"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2106.15512","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2106.15512/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}