1. Department of Functional Molecular Science, School of Mathematical and Physical Science, The Graduate University for Advanced Studies and Institute for Molecular Science, Okazaki 444, Japan, Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060, Japan, Institute for Solid State Physics, The University of Tokyo, Roppongi, Minato-ku, Tokyo 106, Japan, and Department of Chemistry, School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113, Japan