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Organoboron Complexes as Thermally Activated Delayed Fluorescence (TADF) Materials for Organic Light-Emitting Diodes (OLEDs): A Computational Study.

ABSTRACT: We report on organoboron complexes characterized by very small energy gaps (ΔE_ST) between their singlet and triplet states, which allow for highly efficient harvesting of triplet excitons into singlet states for working as thermally activated delayed fluorescence (TADF) devices. Energy gaps ranging between 0.01 and 0.06 eV with dihedral angles of ca. 90° were registered. The spin-orbit couplings between the lowest excited S₁ and T₁ states yielded reversed intersystem crossing rate constants (K_RISC) of an average of 10⁵ s^-1. This setup accomplished radiative decay rates of ca. 10⁶ s^-1, indicating highly potent electroluminescent devices, and hence, being suitable for application as organic light-emitting diodes.

SUBMITTER: Asiri JA

PROVIDER: S-EPMC10574585 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Organoboron Complexes as Thermally Activated Delayed Fluorescence (TADF) Materials for Organic Light-Emitting Diodes (OLEDs): A Computational Study.

Asiri Jamilah A JA Hasan Walid M I WMI Jedidi Abdesslem A Elroby Shaaban A SA Aziz Saadullah G SG Osman Osman I OI

Molecules (Basel, Switzerland) 20231006 19

We report on organoboron complexes characterized by very small energy gaps (ΔEST) between their singlet and triplet states, which allow for highly efficient harvesting of triplet excitons into singlet states for working as thermally activated delayed fluorescence (TADF) devices. Energy gaps ranging between 0.01 and 0.06 eV with dihedral angles of ca. 90° were registered. The spin-orbit couplings between the lowest excited S1 and T1 states yielded reversed intersy ...[more]

PMID: 37836795

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