Theoretical Study on Singlet Fission Dynamics in Slip-Stack-like Pentacene Ring-Shaped Aggregate Models.

We investigate the singlet fission (SF) dynamics of a slip-stack-like pentacene ring-shaped aggregate model, which is constructed by rotating each pentacene unit around its longitudinal axis in an H-aggregate ring. The aggregate size () and rotation angle (α) dependences of SF rates and double triplet (TT) yields are clarified using the quantum master equation method. It is found that there exist optimal ranges of the rotation angle α for each , yielding efficient SF with high SF rates and TT yields.

Theoretical study on the effect of applying an external static electric field on the singlet fission dynamics of pentacene dimer models.

We investigate the effect of applying an external static electric field on the singlet fission (SF) dynamics of pentacene dimer models using quantum chemical calculations and exciton dynamics simulations. It is found that the excitation energies of anion-cation (AC) and cation-anion (CA) pair exciton states in the SF process are significantly stabilized and destabilized, respectively, by applying an external static electric field (F) in the intermolecular direction. As a result, this change of excitation energies is found to accelerate the SF dynamics in pentacene dimer models.