Mechanisms of gas-phase carbonyl complexes M(CO)6 and M2(CO)10 (M = Mo, W) catalyzed WGSR are reported.
The energetic span model is applied to reveal the kinetic behavior of the catalytic cycles.
W2(CO)10 is considered as the most efficient catalyst of our research for WGSR.
εd − EF value is useful as a qualitative activity descriptor in catalysis of WGSR.