1. Beckman Institute, California Institute of Technology, Pasadena, California 91125; Institute de Physique et Chemie des Materiaux de Strasbourg (UM 046 CNRS), 23 rue du Loess, F-67037 Strasbourg Cedex, France; Optical Materials Division, ROI Technology, 2000 Cornwall Road, Monmouth Junction, New Jersey 08852; School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400; Materials Science and Engineering Department, University of Washington, Seattle, Washington 98195...