1. Clarkson Institute of Statistical Physics (CISP) and Department of Physics, Clarkson University, Potsdam, New York 13699-5820
2. Lehrstuhl für Umweltmesstechnik am Engler-Bunte-Institut der Universität Karlsruhe, 76128 Karlsruhe, Germany
3. Department of Chemistry, Ohio State University, Columbus, Ohio 43210-1185
4. Department of Chemistry, Columbia University, New York, New York 10027