The impact of stacking and phonon environment on energy transfer in organic chromophores: computational insights
The impact of stacking and phonon environment on energy transfer in organic chromophores: computational insights
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堆积和声子环境对有机发色团能量转移的影响：计算见解
DOI：
10.1039/d3tc00479a
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发表时间：
2023
影响因子：
6.4
通讯作者：
Sharifzadeh, Sahar
中科院分区：
文献类型：
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作者：
Mukazhanova, Aliya;Negrin-Yuvero, Hassiel;Freixas, Victor M.;Tretiak, Sergei;Fernandez-Alberti, Sebastian;Sharifzadeh, Sahar
由于在光电子学中的许多应用，有机材料中的能量转移得到了广泛的研究。分子组装体中的电子和振动弛豫可能受到堆叠排列或添加将它们结合起来的主链的影响。在这里，我们提出了苝二酰亚胺单体以及面对面堆叠的二聚体和三聚体的光激发动力学的计算研究。通过使用非绝热激发态分子动力学模拟，我们表明非辐射弛豫随着堆叠分子数量的增加而加速。这种效应可以通过影响其相应非绝热耦合的状态之间的能量分裂差异来解释。此外，我们对电子振动动力学的分析表明，通过参与堆叠系统松弛的不同圆锥形交叉点的通道激活了正反馈机制。这种效应涉及一组狭窄的振动简正模式，通过提高振动动力学的效率来加速这一过程。相比之下，添加受生物启发的主链会减慢弛豫速率，因为它参与分子堆叠排列的振动动力学。我们的结果表明，堆叠排列和共同主链可作为调节二酰亚胺基系统和其他分子聚集体的电子和振动弛豫效率的策略。
Energy transfer in organic materials is extensively studied due to many applications in optoelectronics. The electronic and vibrational relaxations within molecular assemblies can be influenced by stacking arrangements or additions of a backbone that unites them. Here, we present the computational study of the photoexcitation dynamics of a perylene diimide monomer, and face-to-face stacked dimer and trimer. By using non-adiabatic excited-state molecular dynamics simulations, we show that the non-radiative relaxation is accelerated with the number of stacked molecules. This effect is explained by differences in the energy splitting between states that impacts their corresponding nonadiabatic couplings. Additionally, our analysis of the vibronic dynamics reveals that the passage through the different conical intersections that participate in the relaxation of the stacked systems, activate a positive feedback mechanism. This effect involves a narrow set of vibrational normal modes that accelerate the process by increasing the efficiency of its vibronic dynamics. In contrast, an addition of a biologically inspired backbone slows down the relaxation rate due to its participation in the vibronic dynamics of the molecular stacking arrangements. Our results suggest the stacking arrangements and common backbones as strategies to modulate the efficiency of electronic and vibrational relaxation of diimide-based systems and other molecular aggregates.