Abstract:
coinage clusters (copper, silver and gold). It is found that charge transfer interactions between the clusters and the alcohol
initiate their reactions allowing a chemisorption step. The binding energy is calculated, whereby ethanol adsorbs very strongly
on Au in comparison to Ag and Cu. The nature of bonding is investigated using natural bond orbital (NBO) analysis and
quantum theory of atoms-in-molecules (QTAIM). The reactive intermediates, activated complexes, transition states, and
bond breaking on icosahedral Au13, Cu13, Ag13 and also triangular Au3, Cu3, Ag3 have been calculated alongside the cycle
kinetics. Furthermore, high resolution mass spectroscopy has been used to study the ethanol coupling reactions over small
Au cluster catalysts. The observation of the coupling products concurs with the kinetic- and thermodynamic- allowed reac tion pathway of Guerbet coupling of ethanol. The highest selectivity for butanol (61%) is obtained after a reaction time of
2 h while the highest ethanol conversion (91%) is obtained after a reaction time of 5 h.
Keywords Coinage Metal
