1. Institute of Materials Chemistry, Tampere University of Technology, P.O. Box 541, 33101 Tampere, Finland, Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan, and Fukui Institute for Fundamental Chemistry, Kyoto University, 34-4, Takano-Nishihiraki-cho, Sakyo-ku, Kyoto 606-8103, Japan