1. Department of Chemistry University of California, Irvine Irvine CA 92697 USA
2. Department of Chemical Engineering and Materials Science University of California, Irvine Irvine CA 92697 USA
3. Department of Electrical and Computer Engineering Boston University Boston MA 02215 USA
4. CNR-IOM Laboratorio TASC Trieste 34149 Italy
5. Faculty for Mathematics and Physics University of Ljubljana Jadranska 19 1000 Ljubljana Slovenia
6. Department of Electrical Engineering Columbia University New York NY 10027 USA
7. Institut J. Stefan Jamova 39 1000 Ljubljana Slovenia
8. Department of Physics University of Trieste Trieste 34128 Italy