1. Contribution from the Department of Chemistry, Waseda University, Tokyo 169, Japan, Nissan ARC Ltd., 1, Natsushima, Yokosuka, Kanagawa 237, Japan, Central Engineering Laboratories, Nissan Motor Co. Ltd., 1, Natsushima, Yokosuka, Kanagawa 237, Japan, and Instrumental Analysis Center of Chemistry, Faculty of Science, Tohoku University, Aramaki Aoba, Aoba-ku, Sendai 980, Japan