Pathways for dissociative methane chemisorption on Pt{110}-(1x2)

Two distinct pathways are characterized for dissociative chemisorption of methane on Pt{110}-(1x2). The transition states are obtained to high precision using a fully unconstrained technique involving hybrid eigenvector-following with variational eigenvector refinement and tangent space minimization. The two paths yield products where methyl occupies a ridge atop site, with the dissociated hydrogen in one of two distinct ridge bridge sites. Both pathways involve simultaneous stretching of a C-H bond and deformation of methane bond angles, in agreement with experimentally observed rate enhancement.