Replication Data for Covalent Control of Excitonic Interactions in Perylene Diimide Trimers: A Computational Study

Covalently tethering chromophores is an emerging strategy to control the structure and function of supramolecular aggregates for organic electronic applications. In this study, we employ first principle calculations to elucidate structure-property relationships in three perylene diimide (PDI) trimer systems: a non-covalent assembly (u-PDI3), a stapled assembly (t-PDI3), and a folded (foldamer) assembly, (s-PDI3) in aqueous solvent. Our results show how tethering controls inter-chromophore geometry, particularly twist angles and slip displacements, which determine electronic coupling patterns. The t-PDI3 system enforces symmetric cofacial alignment with small twist angles, producing high charge-transfer (CT) character across low-lying excited states, strong coupling (0.16-0.17 eV), and the largest exciton bandwidth. In contrast, u-PDI3 features varying electronic transition character and coupling heterogeneity (0.07-0.15 eV), while s-PDI3 has uniform CT character with moderate coupling strength (0.10-0.14 eV). The findings highlight how covalent tethering can be engineered to tune excitonic and charge-transfer properties in pi-stacked molecular aggregates.

共价栓系生色团是一类新兴策略，可用于调控有机电子应用中超分子聚集体的结构与功能。本研究采用第一性原理计算，阐明了三种苝二酰亚胺（perylene diimide, PDI）三聚体体系的构效关系：分别为水相溶剂中的非共价组装体（u-PDI3）、订书钉型组装体（t-PDI3）与折叠型（折叠体）组装体（s-PDI3）。我们的研究结果揭示了栓系如何调控生色团间的几何构型，尤其是扭转角与滑移位移——这两者决定了电子耦合模式。t-PDI3体系可实现具有小扭转角的对称共面排布，在低能激发态中呈现出极强的电荷转移（charge-transfer, CT）特性，拥有较强的电子耦合强度（0.16~0.17 eV）与最宽的激子带宽。与之形成对比的是，u-PDI3展现出多样的电子跃迁特性与不均一的耦合强度（0.07~0.15 eV）；而s-PDI3则拥有均一的电荷转移特性，耦合强度处于中等水平（0.10~0.14 eV）。本研究结果凸显了可通过工程化设计共价栓系策略，来调控π堆叠分子聚集体中的激子与电荷转移特性。