Hyperligated complexes

Octahedral structures of the third kind are those in which d2sp bonds are formed with use of two of the 3d orbitals, leaving only three for occupancy by atomic electrons. Complexes with these structures were formerly described as essentially covalent here we shall describe them as hyperligated complexes (complexes with strong bonds). 

The magnetic method cannot be applied to tripositive chromium, the structures of the two extreme types having the same number of unpaired electrons and entering into resonance with each other. The chemical properties of the chromium complexes indicate that chromium, like the other iron-group elements, forms hyperligating bonds... 

That chromium forms cPsp8 hyperligating bonds with oxalate in the ion [Cr(Ci04)j]+++ has been inferred by C. H. Johnson (Trans. Faraday Soc. 28, 845) [1932]) from the following facts The chromium trioxalate complex and the cobaltic trioxalate complex can be resolved into optical isomers, whereas... 

All the octahedral complexes of the elements of the palladium and platinum groups that have been investigated are diamagnetic, showing the strong tendency of these elements to form hyperligating bonds. 

The nature of the spin-state of the metal ion may be reflected in the metal-ligand bond-lengths of the MLj complex. This is well-exemplified for the hyperligated and hypoligated complexes [CoCNHj), and which have... 

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