Recent progress in the field of molecular magnetism has shown the clear potential for gaining control over the structural building blocks of molecular materials in order to engineer desirable magnetic properties. Our recent work has proved important in demonstrating how structure promotes and controls certain exchange pathways. However, an important variable that we have only just started to exploit is the identity of the atom providing the exchange link between the strongly interacting elements in a structure such as the planes or chains. In this continuation request we propose to complete our investigation of this effect by measuring two compounds where magnetic layers are linked by magnetic ions.