General. Most materials are structurally and chemically complex. Although this complexity tends to hinder a fundamental understanding of their properties, this understanding is nevertheless essential for a wide range of purposes, spanning from new and useful technological materials to aerosol particles in the atmosphere.

Metal clusters and oragnometallic framewoks. It was realized very early that the detailed features of the surface could be the key to catalytic activity,* a notion that has been strengthened throughout the years. In this respect, metal clusters may be suitable models of the imperfect but reactive sites of a catalyst. It is then of interest to learn how reactivity is related to the molecular and electronic structure of a given cluster. The recent demonstration of catalytic activity of size-selected clusters which were soft-landed on a suitable support is particularly illustrative.** Within the centre, we plan to investigate the properties of catalytically important metals in highly diverse environments, including molecular complexes, small gas-phase metal clusters M_n (n = 1 - 30), metal surfaces, metal clusters on solid supports, and complex 3-dimensional structures (organometallic frameworks). This activity will be supported by ongoing work by Mats Tilset and researchers associated with the newly established SFI centre of catalysis at the Department of Chemistry, University of Oslo.

Water clusters and nanodroplets. Very recently (2 February 2007) the Intergovermental Panel on Climate Change published their fourth assessment report.*** About the important issue of the factors which determine climate change they conclude: "Anthropogenic contributions to aerosols (primarily sulphate, organic carbon, black carbon, nitrate and dust) together produce a cooling effect, with a total direct radiative forcing of -0.9 to -0.1 W m^-2 and an indirect cloud albedo forcing of -1.8 to -0.3 W m^-2. These forcings are now better understood ...., but remain the dominant uncertainty in radiative forcing. Aerosols also influence cloud lifetime and precipitation."

This perspective poses a challenge to chemists. Both within the CTCC and through international collaboration, we study the chemical and physical properties of water clusters containing a central ion. Such particles are critical for water droplet nucleation in the atmosphere, and therby cloud formation.


* H. S. Taylor, Proc. R. Soc. London, A 1925, 108, 105; H. S. Taylor, Z. Elektrochem. Angew. Phys. Chem. 1929, 35, 542.
** S. Abbet, K. Judai, L. Klinger, U. Heiz, Pure Appl. Chem. 2002, 74, 1527.
***See http://www.ipcc.ch/for summary and more information. The full report will be published by Cambridge Univ. Press, New York.