1. Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Yoshida Honmachi, Kyoto 606-01, Japan
2. Nara Institute of Science and Technology, 8916-5 Takayama-cho, Ikoma, Nara 630-01, Japan
3. Institute for Chemical Research, Kyoto University, Gokanosho, Uji, Kyoto 611, Japan