Hypoligated and Hyperligated Transition Metal Complexes

The low-energy valence-shell atomic orbitals for the transition metals are the five (iimer) (n-1) d orbitals and the s and three np atomic orbitals. (For atoms of first-row transition metals Sc.Cu, these are the 3d 2 2, 3d 2, 3d,y, 3d, 3d, 4s, 

Chapter 5 Pauling 3-Electron Bonds and Hypoligated Transition Metal Complexes 

Because low-spin has sufficient valence-shell orbitals to form six electron-pair Co-N bonds, may be classified as a hyperligated 

Isoelectronic [Fe(H20)J and [CoFJ are paramagnetic complexes with magnetic moments of 5.3 Bohr magneton the spin-only formula for the magnetic moment n[n + 2) generates a magnetic moment of 4.9 Bohr magneton 

For hypoligated complexes, either of the following valence-bond procedures is sometimes used to describe the metal-ligand o-bonding  

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