Tonami Takayoshi, Sugimori Ryota, Sakai Ryota, Tokuyama Kazuaki, Miyamoto Hajime, Nakano Masayoshi
Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.
Phys Chem Chem Phys. 2021 May 26;23(20):11624-11634. doi: 10.1039/d1cp00880c.
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. In particular, in the tilted- and parallel-type pentacene dimer models, SF rates at F = 0.001 a.u. are predicted to be about 2.3 and 3.0 times as large as those at F = 0.0 a.u. while keeping the TT yields large. The present result contributes to paving the way for novel physical and chemical controls, that is, an external static electric field application and donor/acceptor substitution on SF molecules, of SF dynamics.
我们使用量子化学计算和激子动力学模拟，研究了施加外部静电场对并五苯二聚体模型单重态裂变（SF）动力学的影响。研究发现，在分子间方向施加外部静电场（F）时，SF过程中阴离子-阳离子（AC）和阳离子-阴离子（CA）对激子态的激发能分别显著稳定和不稳定。结果，发现这种激发能的变化加速了并五苯二聚体模型中的SF动力学。特别是，在倾斜型和平行型并五苯二聚体模型中，预测在F = 0.001 a.u.时的SF速率约为F = 0.0 a.u.时的2.3倍和3.0倍，同时保持TT产率较高。目前的结果有助于为SF动力学的新型物理和化学控制，即外部静电场应用和SF分子上的供体/受体取代，铺平道路。
