1. Department
of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-747, Republic of Korea
2. Department
of Applied Chemistry, Hanyang University, Ansan 426-791, Republic of Korea
3. LG Chem., 188 Munji-ro, Yuseong-gu, Daejeon 305-738, Republic of Korea