The Electronic Structure of the Protonated Methane CH⁺₅

Abstract

The electronic structure of the ground state of the protonated methane CH⁺₅ is studied by the Heitler-London-Slater-Pauling method extended by Voge and by Kotani and Siga. The wave functions are constructed without the assumption of the electron pair bond and with taking (2s)²(2p)², (2s)(2p)³, and (2p)⁴ configurations of the carbon atom into account. Assuming a probable model for this ion, we obtain seventeen ¹A₁′ states. The energy matrix for these states is computed by means of the representation matrices of the symmetric group. By solving the secular equations thus obtained for two different sets of parameters, the binding energy (or the proton affinity) and the equilibrium proton-carbon distance are estimated.