1. Material Design and Characterization Laboratory, Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
2. Solid State Physics and Chemistry Laboratory, Division of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
3. Max Planck Institute for Solid State Research, Heisenbergstrasse 1, D-70569 Stuttgart, Germany
4. Beam Line Station, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
5. Toyota Physical and Chemical Research Institute, Nagakute, Aichi 480-1192, Japan