1. Department of Chemistry; Tokyo Institute of Technology; O-okayama, Meguro-ku Tokyo 152-8551 Japan
2. Present address: Department of Chemistry; Faculty of Science; Tokyo University of Science; Tokyo 162-8601 Japan
3. Research & Utilization Division; Japan Synchrotron Radiation Research Institute; Kouto Sayo-cho Sayo-gun, Hyogo 679-5198 Japan