Molecular rotational conformation controls the rate of singlet fission and triplet decay in pentacene dimers.

ABSTRACT: Three pentacene dimers have been synthesized to investigate the effect of molecular rotation and rotational conformations on singlet fission (SF). In all three dimers, the pentacene units are linked by a 1,4-diethynylphenylene spacer that provides almost unimpeded rotational freedom between the pentacene- and phenylene-subunits in the parent dimer. Substituents on the phenylene spacer add varying degrees of steric hindrance that restricts both the rotation and the equilibrium distribution of different conformers; the less restricted conformers exhibit faster SF and more rapid subsequent triplet-pair recombination. Furthermore, the rotational conformers have small shifts in their absorption spectra and this feature has been used to selectively excite different conformers and study the resul

SUBMITTER: Ringstrom R 

PROVIDER: S-EPMC9067590 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature