Vibrational Damping Reveals Vibronic Coupling in Thermally Activated Delayed Fluorescence Materials.

ABSTRACT: We investigate a series of D-A molecules consisting of spiro[acridan-9,9'-fluorene] as the donor and 2-phenylenepyrimidine as the acceptor. In two of the materials, a spiro center effectively electronically isolates the D unit from (consequently) optically innocent yet structurally influential adamantyl side groups. In a third material, adamantyl groups attached directly to the acceptor strongly influence the electronic properties. Steady-state and time-resolved photophysical studies in solution, Zeonex polymer matrix, and neat films reveal that the substituents impact the efficiency of vibronic coupling between singlet and triplet states relevant to reverse intersystem crossing (rISC) and thermally activated delayed fluorescence (TADF), without significantly changing the singlet-triplet g

SUBMITTER: Hempe M 

PROVIDER: S-EPMC8273894 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature