For the 6-PF6 -complex, we could not optimize the 12CN complex and the 11CN complex is most abundant with a good amount of 10CN conformer. The presence of seventh PF6 -changes the entire scenario making one of the 10CN conformer as the predominant one. From these results, we can conclude that with the increase of PF6 -numbers, the crowding around the Nd-center increases, which favors the lower CN over the higher one.