1. Contribution from the Department of Chemistry and The Center for Fundamental Materials Research, Michigan State University, East Lansing, Michigan 48824 , Bruker, Madison, WI, Laboratoire de Physique des Solides, URA 02, Bat 510 Université Paris-Sud Orsay Cedex, 91405 France, and Institut de Ciencia de Materials de Barcelona (CISC), Campus de la UAB, E-08193 Bellaterra, Spain