1. Department of Chemistry, Brock University, 500 Glenridge Avenue, St. Catharines, L2S 3A1 Ontario, Canada, Departamento de Quimica Fisica y Analitica, Universitat Jaume I, Avenida Sos Baynat s/n, 12701 Castellón, Spain, and Institut de Microtechnique, Rue Emile-Argand 11, Bâtiment G, Case Postal 158, CH-2009 Neuchâtel, Switzerland