四氯化苯醌-二苯撑体系的光诱导电子转移研究

Theoretical Investigation on Photoinduced Electron Transfer between Chloranil and Biphenylene

用从头算方法对四氯化苯醌 -二苯撑体系分子间相互作用进行了理论计算研究 .用MP2 /6 3 1G 方法 ,分别优化电子给体二苯撑 ,受体四氯化苯醌的稳定构型 ,用同样的方法优化配合物的层间距得到其最稳定构型 ,并计算了BSSE校正后的电子给受体配合物的稳定化能 .用CIS/6 3 1++G 方法 ,计算了给体、受体及配合物的电子激发态 .理论计算验证了给体和受体间能形成稳定的电子给受体配合物 ,该配合物受光激发能直接产生电荷转移态 .在球孔穴近似和点偶极近似下 ,对电荷转移吸收的理论计算结果进行了非平衡溶剂化能校正 .

Theoretical calculation has been performed for the photoinduced electron transfer between chloranil and biphenylene. The center-center distance between the donor and acceptor of the complex has been optimized by using MP2 method, and the counterpoise method has been adopted to consider the basis set superposition error. Four low-lying excited singlet states of chloranil-biphenylene (CL-BP) complex have been investigated by using the method of configuration interaction singles. It is concluded that CL and BP can form a stable electron donor-acceptor complex and light absorption can directly produce excited charge transfer state. Based on the approximation of spherical cavity and point dipole, the solvation correction of the absorption spectrum has been made for the charge transfer transition. The red shift of 0.443 eV was predicted. The result shows that the theoretical calculation agrees well with the experimental observations.