1. Department of Chemistry, School of Molecular Science‐BK21 and Center for Molecular Design and Synthesis, Korea Advanced Institute of Science and Technology, Daejeon, 305‐701, Republic of Korea, Fax: +82‐42‐869‐2810
2. Department of Chemistry, School of Molecular Science‐BK21 and Center for Advanced Functional Polymers, Korea Advanced Institute of Science and Technology, Daejeon, 305‐701, Republic of Korea