1. Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, Instituto de Investigaciones Metalurgicas, Universidad Michoacana de San Nicolás de Hidalgo, Ciudad Universitaria, Morelia Michoacán, 58060, México, Department of Chemistry, Tsinghua University, Beijing, 100084, China, and Centro de Investigaciones en Optica, A.P. 1-948, Leon Gto. 37160, México