A series of 4--selenopheno[3,4-c]pyrrole-4,6(5-)-dione based chromophores () was designed the introduction of selenophene units (n = 2–7) in the π–spacer of reference compound () owing to growing demand of non-fullerene based organic solar cells. The influence of selenophene π–spacer on photovoltaic properties of entitled molecules was explored by utilizing CAM-B3LYP/6-311G (d,p) functional. All the designed compounds were found with lesser values of energy gaps (4.342–3.904 eV) as compared to (4.764 eV). Similarly, their absorption values were found in the visible region (523.560–533.403 nm) in dichloromethane solvent. Moreover, the entitled chromophores exhibited lower binding energies (1.895–1.566 eV) with higher open circuit voltage values which supported their excellent charge transference properties. The unique properties like least value of bandgap (3.904 eV) with greater charge transfer phenomena were examined for due to the presence of most elongated chain of selenophene-based π–spacer. The density of state and transition density matrix maps illustration further confirmed the efficient charge transfer in . Overall, these findings disclosed that by utilizing selenophene π–spacer, photovoltaic properties of organic materials can be efficiently improved.

中文翻译：

---

硒吩 π 连接体对吡咯-4,6(5-H)-二酮基发色团光伏特性的影响：量子化学研究

设计了一系列基于 4--selenopheno[3,4-c]pyrrole-4,6(5-)-dione 的发色团 ()，在参考 π-间隔基中引入了 selenophene 单元 (n = 2–7)由于非富勒烯有机太阳能电池的需求不断增长，化合物（）。利用 CAM-B3LYP/6-311G (d,p) 泛函探讨了硒吩 π-间隔基对标题分子光伏特性的影响。与 (4.764 eV) 相比，所有设计的化合物都具有较小的能隙值 (4.342–3.904 eV)。同样，在二氯甲烷溶剂中，它们的吸收值位于可见光区域（523.560–533.403 nm）。此外，该发色团表现出较低的结合能（1.895-1.566 eV）和较高的开路电压值，这支持了其优异的电荷转移特性。由于存在最细长的基于硒吩的 π 间隔基链，因此检查了独特的性质，例如带隙最小值 (3.904 eV) 和更大的电荷转移现象。状态密度和跃迁密度矩阵图的说明进一步证实了 中的有效电荷转移。总的来说，这些发现表明，通过利用硒吩π-间隔基，可以有效提高有机材料的光伏性能。