1. Center for Nanochemistry, Beijing
National Laboratory for Molecular Sciences, Key Laboratory for the
Physics and Chemistry of Nanodevices, State Key Laboratory for Structural
Chemistry of Unstable and Stable Species, College of Chemistry and
Molecular Engineering, Peking University, Beijing 100871, China
2. Departamento de Fisica, Universidade Federal de Minas Gerais, Belo Horizonte,
MG, Brazil 30123970
3. Departamento
de Física, Universidade Federal de Viçosa, Viçosa,
MG, Brazil 36570000