Monoatomic Ligands

The main variables here are the capacity of the ligand to provide single- or multiple-atom bridging and the presence or absence of a monoatomic ligand at the centre of the cube. A central octuply-bridging ligand probably provides mechanical stability. 

In the case of simple entities such as monoatomic ligands the multiplicative prefixes di, tri, tetra, penta, etc., are used. 

With the exception of the ligand FI, for which there is only a single valence orbital Ish to consider (a a interaction), one must treat aU the valence s and p orbitals on a monoatomic ligand A. Now the s orbital is usually much lower in energy than the d orbitals on the metal, especially... 

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