To better understand the relationships between the microstructure and the optoelectronic characteristics of the electron acceptor and to meet the needs of donor-acceptor materials with excellent optical properties for solar cell, a series of acceptor molecules with A'-π-A-π-Atype are designed. In these molecules, the core framework of benzothiadiazole is used as an acceptor (A), three kinds of conjugated heterocyclics (A') with different abilities of electron-withdrawing and steric effects are applied as the terminals, and various conjugated structures, such as the double bond, thiophene, benzothiophene and vinyl thiophene, are utilized as π-bridge, respectively. Their geometric configurations, the characteristics of frontier mo- lecular orbital, optical properties, as well as the electronic reorganization energy are predicted by DFT-B3LYP and TD-DFT-CAM-B3LYP. Solvent effects from acetone and chlorobenzene on molecular properties are studied. Furthermore, the Donor-Acceptor (D-A) interfaces are respectively constructed by combining the excellent acceptors with the selected two donors. The DFT-D3 method is used to scan the binding energy of D-A complex, in order to determine the stacked displace- ment of the interface. The degree of interface recombination is evaluated by calculating electronic coupling (Vif) between HOMO of donors and LUMO of acceptors. The results show that modifying benzothiadiazole with a reasonable substituent is an effective way to adjust LUMO energy levels and lead to the noticeable variation of the energy gap. Combining planar electron acceptor materials (A'-π-A-π-Atype) with non-planar electron donor materials (D), to form the optical active layer is a practical approach for preventing interface recombination and achieving high open-circuit voltage (Voc). Considering ΔEL, Vif, light absorption efficiency, and solvation effect, D1-1aγ and D1-2aγ combinations are the most promising candi- dates of optical active layer materials in organic solar cell. Keywords benzothiadiazole derivatives; electronic acceptors; Donor-Acceptor interface; electronic coupling; the power conversion efficiency

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苯并噻二唑衍生物电子受体的分子设计和供体-受体材料的匹配

为了更好地理解电子受体的微观结构与光电特性之间的关系，满足太阳能电池对具有优异光学性能的供体-受体材料的需求，一系列具有A'-π-A-π-A型的受体分子被设计。在这些分子中，以苯并噻二唑的核心骨架为受体（A），以三种吸电子能力和空间效应不同的共轭杂环（A'）为末端，各种共轭结构，如双键噻吩、苯并噻吩和乙烯基噻吩分别用作π-桥。它们的几何构型、前沿分子轨道特征、光学性质、以及电子重组能由 DFT-B3LYP 和 TD-DFT-CAM-B3LYP 预测。研究了丙酮和氯苯的溶剂对分子特性的影响。此外，通过将优秀的受体与选定的两个供体结合，分别构建供体 - 受体（DA）界面。DFT-D3 方法用于扫描 DA 复合物的结合能，以确定界面的堆叠位移。通过计算供体的 HOMO 和受体的 LUMO 之间的电子耦合 (Vif) 来评估界面复合的程度。结果表明，用合理的取代基修饰苯并噻二唑是调节LUMO能级并导致能隙显着变化的有效方法。结合平面电子受体材料（A' -π-A-π-Atype) 与非平面电子供体材料 (D)，形成光学活性层是防止界面复合和实现高开路电压 (Voc) 的实用方法。考虑到ΔEL、Vif、光吸收效率和溶剂化效应，D1-1aγ和D1-2aγ组合是有机太阳能电池中最有前途的光学活性层材料候选。关键词苯并噻二唑衍生物；电子受体；供体-受体接口；电子耦合；电源转换效率 D1-1aγ 和 D1-2aγ 组合是有机太阳能电池中最有前途的光学活性层材料候选者。关键词苯并噻二唑衍生物；电子受体；供体-受体接口；电子耦合；电源转换效率 D1-1aγ 和 D1-2aγ 组合是有机太阳能电池中最有前途的光学活性层材料候选者。关键词苯并噻二唑衍生物；电子受体；供体-受体接口；电子耦合；电源转换效率