1. Department of Chemistry, National Chung Hsing University, Taichung 402, Taiwan
2. Institute of Polymer Science and Engineering, National Taiwan University, Taipei 10617, Taiwan
3. ICGM, University of Montpellier, CNRS, ENSCM, Montpellier 34293 Cedex
5, France
4. Institut Universitaire de France (IUF), 1 Rue Descartes, Paris Cedex 05 75231, France