The bonding of 1-electron ligands to transition metals

The M-C system has the local symmetry Coov and in this symmetry group the metal and carbon orbitals can always take part in both a- and n-bonding. 

Symmetiy Metal orbitals Ligand orbitals Bond type 

It is commonly agreed that in metal-alkyl (Rh) bonds there is little n-contribution to the bonding. This is because the and Py orbitals of the a-carbon atom are fully involved in bonding with the carbon or hydrogens which are also attached to it. 

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