1. Department of Chemistry, Chonnam National University, 300 Yongbong-dong, Buk-gu, Gwangju, 500-757, Republic of Korea, ICx Nomadics, Inc., 215 First Street, Suite 105, Cambridge, Massachusetts 02142, and Advanced Materials Division, Korea Research Institute of Chemical Technology, 100 Jang-dong, Yuseong-gu, Daejeon, 305-600, Republic of Korea