1. Molecular Spectroscopy Laboratory, Kanagawa Academy of Science and Technology (KAST), KSP East 301, 3-2-1 Sakato, Kawasaki 213, Japan (C.E., V. D., S.U., H.H.); Institut für Physikalische Chemie, Universität Würzburg, Marcusstr. 9-11, D-97070 Würzburg, Germany (C.E., V.D., W.K.); and Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, 560012, India (S.U.)