Supplementary Material (ESI) for Physical Chemistry Chemical Physics This journal is (c) The Owner Societies 2010 1 Supplementary information O 2 adsorption and dissociation on neutral, positively and negatively charged Au n (n = 5-79) clusters Alberto Roldán, a,b Josep Manel Ricart, b Francesc Illas, a Gianfranco Pacchioni c a) Departament de Química Física & Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, C/Martí i Franquès 1, 08028 Barcelona, Spain b) Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, C/Marcel.lí Domingo s/n, 43007 Tarragona, Spain c) Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi 53, I-20125 Milano, Italy For each cluster and charge state considered in this work, we report the full set of optimized geometries, thermodynamic stabilities and transition state barriers. The material is organized according to cluster size (Au n , n = 5, 13, 25, 38, 55 and 79). We also report in a schematic representation the binding energy (E B ) defined in equation 1, the activation barrier (ΔE # ), i.e. the difference between the energy of the transition state and the initial state, and the reaction energy (E R ), defined as the energy difference between the final state and the initial state. ( ) 2 O Au sys B E E E E n + - = Eq. 1 The O 2 dissociation profiles are plotted for each charge state: dashed-line cationic cluster, solid-line neutral cluster, dotted-line negatively charged cluster. Ionization potential (in red-dashed) and electron affinity (in blue-dot) are also shown.