Department of Chemistry, Faculty of Science, Ankara University, 06100, Ankara, Turkey.
, İstanbul, Turkey.
J Mol Model. 2020 Sep 27;26(10):289. doi: 10.1007/s00894-020-04541-y.
Herein, the HOMO-LUMO energy gaps (Eg) and UV spectra of benzo[1,2-c:4,5-c']bis([1,2,5]thiadiazole (BBT) and [1,2,5]thiadiazolo[3,4-g]quinoxaline (TQ)-based donor-acceptor-donor type-conjugated polymers were computed by using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) at B3LYP/6-31G(d,p) level. The donor groups consist of thiophene (TH), 3,4-ethylenedioxythiophene (EDOT), and 3,4-propylene dioxythiophene (ProDOT) units and the bisthiadiazole and thiadiazoloquinoxaline were chosen as electron acceptor groups. To examine the effects of the alkyl side chain on the molecular structure and Eg of the polymer, methyl groups were added at the 3,4-, 2,3-, and 3,3-positions of TH, EDOT, and ProDOT donor groups, respectively. Our calculated HOMO-LUMO energy gaps are in the range of 0.05 to 1.37 eV. The calculation results show that the energy gaps are in line with the available experimental values. The novel BBT and TQ derivatives with improved optical and electronic properties may find use in electronic applications. Graphical abstract.
本文通过密度泛函理论（DFT）和含时密度泛函理论（TD-DFT）在 B3LYP/6-31G(d,p)水平上计算了苯并[1,2-c:4,5-c']双([1,2,5]噻二唑（BBT）和[1,2,5]噻二唑并[3,4-g]喹喔啉（TQ）基给体-受体-给体型共轭聚合物的最高占据轨道-最低未占据轨道能隙（Eg）和紫外光谱。供体基团由噻吩（TH）、3,4-亚乙基二氧噻吩（EDOT）和 3,4-亚丙基二氧噻吩（ProDOT）单元组成，双噻二唑和噻二唑并喹喔啉被选为电子受体基团。为了研究烷基侧链对聚合物分子结构和 Eg 的影响，分别在 TH、EDOT 和 ProDOT 供体基团的 3,4-、2,3-和 3,3-位添加了甲基基团。我们计算的 HOMO-LUMO 能隙范围为 0.05 至 1.37 eV。计算结果表明，能隙与可用的实验值相符。具有改善的光学和电子性能的新型 BBT 和 TQ 衍生物可能在电子应用中找到用途。
