1. Department of Chemistry, Graduate School of Science; Tohoku University, Aramaki; Aoba-ku Sendai 980-8578 Japan
2. Department of Chemistry and Bioengineering, Graduate School of Engineering; Iwate University; Morioka 020-8551 Japan
3. Research and Analytical Center for Giant Molecules, Graduate School of Science; Tohoku University; Sendai 980-8578 Japan