Hemme complex

[EriMizuguchi2K]

For this hemme complex, would we just find the coordination by counting the number of bonds the iron makes? Also, would this give us the answer to what kind of polydentate the ligand is acting as because if the coordination number is 4, then it would be a tetradentate? Also, how would we know that the expected geometry is square planar since there's only four bonds shown? Sorry if this was a lot to answer at once!

[Lucas Koch 1I]

Yes, the coordination number is the amount of bonds the central metal makes. Yes, it gives the kind of polydentate in this case because there is only one molecule. With coordination compounds with four bonds it can have either tetrahedral or square planar geometry and Dr. Lavelle said in lecture that the only way to tell is to look at the diagram given. In the case of the heme complex you are correct though that it is square planar.