1. Department of Chemistry, National Taiwan University, and Institute of Atomic and Molecular Sciences, Academia Sinica, P.O. Box 23-166, Taipei, Taiwan 10764, Republic of China (K.-D.S., K.-C.L.); and Institute of Atomic and Molecular Sciences, Academia Sinica, P.O. Box 23-166, Taipei, Taiwan 10764, Republic of China (W.-T.L.)