I want to calculate the adsorption of CO on Si-doped graphene using DMOL3 in Materials Studio. To construct the geometry of the adsorbed CO on the graphene layer, I first replaced a carbon atom in the 5 x 5 supercell of graphene with silicon. To position the CO molecule above it, I first draw the oxygen atom by forming its bond with silicon and then create an O-C bond to form the CO molecule. In the next step, I removed the O-Si bond and performed geometry optimization to compute the physisorption energy. Is this approach (of constructing structure) correct?

NOTE: While reproducing some published papers during my practice using the mentioned approach, my generated results were very close to results in papers.