Hi dear colleagues

I need to your help.

I am doing some simulations on Si-doped in graphene for CO catalytic oxidation. In these simulations I need to calculate adsorption energy for "CO2" and "CO2+N2" on this catalyst.

I know CO+N2O---> N2+CO2 and Ea= -86 Kcal/mol. But I could not get it. My obtained activation energy is around -10 Kcal/mol.

And also, for N2 and CO2 adsorption on Si-doped in graphene the activation energy is around -82 Kcal/mol but my obtained activation energy is around -6.6 Kcal/mol.

I did more than 40 simulations but I could not obtained right results. Do you think I have to consider some important points that I do not know about them?

Thank you very much

best regards

Reza