1. College of Physics and Information Engineering & College of Chemistry and Environmental Science, Henan Normal University, Xinxiang, Henan 453007, China
2. Department
of Chemistry − Ångström Laboratory, Uppsala University, Box 537,
SE-75121 Uppsala, Sweden
3. Department of Theoretical Chemistry, Royal Institute of Technology, Roslagstullsbacken 15,
S-106 91 Stockholm, Sweden