Reaction path description of the vinylidene–acetylene isomerization

Abstract

The vinylidene–acetylene isomerization reaction has been studied using a reaction path formalism with one and three degrees of freedom. In the 1D calculation various zero point corrections have been applied to account for the influence of the other vibrational modes. Furthermore we used and tested a simple scanning method to obtain the reaction path potential. The 3D calculation has been done with the help of a locally harmonic approximation of suitable coordinates around the reaction path coordinate. This calculation is compared with a full 3D reference calculation with respect to spectra, eigenfunctions, lifetimes, and time-dependent quantities. We find a satisfactory agreement between the harmonic approximation and the full 3D calculation. Furthermore we find that the isomerization of HDC₂ preferably runs through the ‘channel’ where the hydrogen atom moves.