1. Department of Chemistry, Natural and Applied Sciences, University of WisconsinGreen Bay, Green Bay, Wisconsin 54311, Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, New York 12180, Institute of Spectroscopy, Russian Academy of Sciences, Moscow Reg., Troitsk 142190, Russia, and Department of Chemistry, University of California, Riverside, California 92521