1. Department of Chemistry, University of Virginia, Charlottesville, Virginia 22901, United States
2. Department of Physics, Eberly College of Science, The Pennsylvania State University, Penn State
Berks, P.O. Box 7009, Reading, Pennsylvania 19610-6009, United States
3. Quantum Chemistry Department, Institute of Chemistry, St Petersburg State University, 7-9 Universitetskaya Naberezhnaya, St Petersburg 199034, Russia