Using the density functional theory (DFT) method, the electronic and optical properties of the most stable conformers of the di(selenophen-2-yl) thieno[3,4-c]pyridine (Se-PT-Se) monomer and its oligomers were studied. Optical properties in the ultraviolet and visible regions are determined using the non-stationary theory of the density functional (TD-DFT). By extrapolating the results of DFT obtained for oligomers, it was shown that the band gap for the donor-acceptor-donor conjugated polymer based on [1,2,5]thiadiazole[3,4-c]pyridine is in the range 1.1-1.2 eV, which is consistent with experimental data. The study allowed us to propose a new donor-acceptor-donor conjugated polymer for organic solar cells.

中文翻译：

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供体-受体-供体[1,2,5]噻二唑并[3,4-c]吡啶共轭聚合物太阳能电池应用的DFT研究

使用密度泛函理论 (DFT) 方法，研究二 (硒酚-2-基) 噻吩并 [3,4-c] 吡啶 (Se-PT-Se) 单体及其低聚物最稳定构象异构体的电子和光学性质被研究。紫外和可见光区域的光学特性使用非平稳密度泛函理论 (TD-DFT) 确定。通过对低聚物获得的 DFT 结果进行外推，表明基于 [1,2,5] 噻二唑 [3,4-c] 吡啶的供体-受体-供体共轭聚合物的带隙范围为 1.1- 1.2 eV，与实验数据一致。该研究使我们能够提出一种用于有机太阳能电池的新型供体-受体-供体共轭聚合物。