Impact of Electron Delocalization on the Nature of the Charge-Transfer States in Model Pentacene/C60 Interfaces: A Density Functional Theory Study
Impact of Electron Delocalization on the Nature of the Charge-Transfer States in Model Pentacene/C60 Interfaces: A Density Functional Theory Study
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DOI：
10.1021/jp5074076
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发表时间：
2014-11
影响因子：
3.7
通讯作者：
Bing Yang;Yuanping Yi;Cairong Zhang;S. Aziz;V. Coropceanu;J. Brédas
中科院分区：
文献类型：
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作者：
Bing Yang;Yuanping Yi;Cairong Zhang;S. Aziz;V. Coropceanu;J. Brédas
电子离域效应已被认为在有机光伏器件的光电流产生中发挥关键作用。在这里，我们研究了在由几个并五苯分子和一个富勒烯（C60）分子组成的模型复合物（代表供体/受体异质结）的情况下，电荷离域对电荷转移（CT）状态性质的作用。 CT 态的能量通过时间相关密度泛函理论 (TD-DFT) 进行检查，使用长程校正泛函 ωB97X 和优化的距离分离参数 ω。我们提供了分子堆积（即界面供体/受体方向）、系统尺寸和分子间相互作用如何影响 CT 态性质的一般描述，这些特征对于理解电荷分离机制非常重要。
Electronic delocalization effects have been proposed to play a key role in photocurrent generation in organic photovoltaic devices. Here, we study the role of charge delocalization on the nature of the charge-transfer (CT) states in the case of model complexes consisting of several pentacene molecules and one fullerene (C60) molecule, which are representative of donor/acceptor heterojunctions. The energies of the CT states are examined by means of time-dependent density functional theory (TD-DFT) using the long-range-corrected functional, ωB97X, with an optimized range-separation parameter, ω. We provide a general description of how the nature of the CT states is impacted by molecular packing (i.e., interfacial donor/acceptor orientations), system size, and intermolecular interactions, features of importance in the understanding of the charge-separation mechanism.