1. Center for Computational Science, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
2. Department of Materials Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
3. Department of Advanced Materials Science, University of Tokyo, Kashiwa-no-ha, Kashiwa 227-8561, Japan