Modifying the Plane Angle

To change the relative orientation of two bidentate ligands, we can change the plane angle. The planes are defined by two sets of three atoms, the central one being present in both sets. In this case this will, of course, be the metal atom.

Select, in order, the two nitrogens on ligand one, the metal atom, and the nitrogens
     on the second ligand.
Change the plane angle to 0 and 90 degrees, respectively

In this way, you can easily change the environment around the metal from square planer to tetrahedral. This feature works as long as you choose the atoms in right order, and if the defined planes can freely rotate relative to each other.