论文标题
基于波函数的动态分析与分子内单线裂变中的自由三胞胎的产量分析
Wavefunction-Based Analysis of Dynamics Versus Yield of Free Triplets in Intramolecular Singlet Fission
论文作者
论文摘要
在几种分子内单裂裂变材料中的实验表明，三胞胎 - 三个旋转biexciton的寿命要比最近更长，直到最近，可以在其分离为自由三重情况下之前将Biexciton歼灭的损失机制。我们已经对假设苯苯连接的蒽分子的激发状态波函数进行了多体计算，以更好地理解被研究为潜在的单裂裂变候选物的较大齿轮的二聚体的连接器依赖性行为。这些计算揭示了我们显示的意外特征，这些特征将其延续到实际共价五苯二聚体中。相关的三胞胎旋转biexciton和免费三重态的解离可能很难在乙烯二聚体中很难在三胞胎旋转biexciton的形成确实是超快的。相反，相对较慢的Biexciton组可能表明较小的自旋Biexciton结合能和更大的游离三胞胎产量。当前可用的实验结果似乎支持了这一结论。这两种不同的行为是否是光学旋风产生的不同机制的后果是一个有趣的理论问题。
Experiments in several intramolecular singlet fission materials have indicated that the triplet-triplet spin biexciton has a much longer lifetime than believed until recently, opening up loss mechanisms that can annihilate the biexciton prior to its dissociation to free triplets. We have performed many-body calculations of excited state wavefunctions of hypothetical phenylene-linked anthracene molecules to better understand linker-dependent behavior of dimers of larger acenes being investigated as potential singlet fission candidates. The calculations reveal unanticipated features that we show carry over to the real covalently-linked pentacene dimers. Dissociation of the correlated triplet-triplet spin biexciton and free triplet generation may be difficult in acene dimers where the formation of the triplet-triplet spin biexciton is truly ultrafast. Conversely, relatively slower biexciton formation may indicate smaller spin biexciton binding energy and greater yield of free triplets. Currently available experimental results appear to support this conclusion. Whether or not the two distinct behaviors are consequences of distinct mechanisms of triplet-triplet generation from the optical singlet is an interesting theoretical question.
