论文部分内容阅读
采用密度泛函理论,在B3LYP/6-31G(d)水平下,对基于苯并[1,2-b:4,5-b’]二噻吩(BDT)为电子供体,thieno[3,4-b]pyrazine(TP),thieno[3,4-b]thiadiazole(TD),dithieno[3,4-b:3’,4’-e]pyrazine(DTP)和[1,2,5]thiadiazolo[3,4-e]thieno[3,4-b]pyrazine(TTP)为电子受体的低聚物和聚合物进行了理论计算。为了了解其导电性质,文中不仅计算了二面角、分子内的电荷传输、中心键键长和中心键电荷密度,还分析了核独立化学位移。结果显示:随着聚合链增长,共轭程度不断增加。NICSs值显示:中心环比边环的共轭程度更大。聚合物的能带结构表明:(DTPBDT)_n和(TTPBDT)_n拥有非常低的带隙(分别为0.53和0.40 eV)且拥有比较宽的带宽,因此可以做为潜在的导电材料。
The structures of thieno [3, 5-b ’] dithiophene (BDT) as electron donors at B3LYP / 6-31G (d) 4-b] pyrazine (TP), thieno [3,4-b] thiadiazole (TD), dithieno [3,4- b: 3 ’, 4’-e] Thiadiazolo [3,4-e] thieno [3,4-b] pyrazine (TTP) has been theoretically calculated for oligomers and polymers of electron acceptors. In order to understand its conductivity properties, not only the dihedral angle, intramolecular charge transport, central bond length and central bond charge density were calculated, but also nuclear independent chemical shifts were analyzed. The results show that as the polymerization chain increases, the degree of conjugation increases. NICSs values show that the center ring has a greater degree of conjugation than the edge ring. The band structures of the polymers indicate that (DTPBDT) _n and (TTPBDT) _n have very low bandgaps (0.53 and 0.40 eV, respectively) and have a relatively wide bandwidth and therefore can be potential conductive materials.