Theoretical modeling of dissociative addition of an H2 molecule to doped aluminum clusters FeAl12 and CoAl12

Abstract

The potential energy surfaces (PES) of the reactions FeAl₁₂ + Н₂ → FeН₂Al₁₂ (1) and CoAl₁₂ + Н₂ → CoН₂Al₁₂ (2) of dissociative addition of an H₂ molecule to Fe- and Co-doped aluminum clusters have been calculated by the density functional theory method. Local minima on the PES in the vicinity of low-lying isomers, intermediates, and transition states have been found, and their structural and spectroscopic characteristics and energies have been calculated. The energies of the successive stages of the catalytic cycle have been evaluated, and the channels corresponding to the minimum energy path of the reactions have been studied. Differences between the structural characteristics and energies of key structures in reactions (1) and (2) have been considered. The results are compared with previous calculations of the PES of hydrogenation reactions performed for related clusters doped with nickel and titanium atoms.