1. Department of Chemistry and Southampton Liquid Crystal Institute, University of Southampton, Highfield, Southampton, SO17 1BJ, United Kingdom
2. Institut für Physikalische Chemie, Universität Freiburg, Albertstr. 21, 79104 Freiburg, Germany
3. UMR 168, CNRS, Section de Recherche, Institut Curie, 11, rue Pierre-et-Marie Curie, 75231 Paris Cedex 05, France
4. Liquid Crystal Institute, Kent State University, Kent, Ohio 44242-0001