Theoretical study on the reactions of Nb and Nb+ with CO2 in gas phase

Density functional theory calculations have been performed to explore the potential energy surfaces of C? O bond activation in CO₂ molecule by gas‐phase Nb atom and Nb⁺ cation for better understanding the reaction mechanism of second‐row metal with CO₂. The minimum‐energy reaction path is found to involve the spin inversion in the different reaction steps. This potential energy curve‐crossing dramatically affects the reaction energetic. The present results show that the mechanism is insertion‐elimination mechanism along the C? O bond activation reaction. All theoretical results not only support the existing conclusions inferred from early experiment but also complement the pathway and mechanism for this reaction. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011