1. Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo, Norway, SINTEF Materials and Chemistry, P.O. Box 124, Blindern, N-0314 Oslo, Norway, Laboratory of Inorganic Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland, and Department of Chemistry and Centre for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo, Norway