Methane dehydrogenation by niobium ions: a first-principles study of the gas-phase catalytic reactions

Abstract

The issue of reactivity differences of the ions Nb+ and Nb2+ toward methane (CH4 + Nb+ → NbCH2 + + H2 and CH4 + Nb2+ → NbCH2 2+ + H2) is addressed using CCSD(T)//MP2 and CCSD(T)//B3LYP calculations. A thorough description of the reaction mechanisms and analyses of the geometrical structures, chemical bonds, and molecular orbitals provide important insights into the chemistry of the niobium species. The overall results indicate highly labile kinetics and more favorable thermochemical conditions for Nb2+. The NBO, AIM, and FERMO analyses provide a better understanding of the reactivity differences in the niobium reactions.