Catalysed cyclotrimerisation of acetylene: a computational study

Abstract

Ab initio local density functional computations of electronic structure are used to investigate the mechanism of the cyclotrimerisation of acetylene catalysed by extraframework ions of nickel in zeolite-Y. Criteria based on the optimisation of orbital overlap allow us to arrive at the most favourable orientation of the reactants for the reaction to ensue. Key intermediates in the possible reaction pathway are identified and detailed information is derived on the nature of the bonding between acetylene and Ni²⁺ and the way it changes during the course of the trimerisation.