1. Department
of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1
Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
2. Keio
Institute of Pure and Applied Science (KiPAS), Keio University, 3-14-1
Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
3. JST, ERATO, Nakajima Designer Nanocluster Assembly Project, 3-2-1 Sakado, Takatsu-ku,
Kawasaki 213-0012, Japan