1. School of Chemistry, University of Nottingham, University Park, NG7 2RD, U.K., Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255, Central Laser Facility, CCLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire, OX11 0QX, U.K., Department of Chemistry, The University of Memphis, Memphis, Tennessee 38152-3550, and Department of Chemistry, University of Belgrade, Studentski trg 16, P.O. Box 158, 11001 Belgrade, Serbia