Ligand field theory

   Although we shall not be concerned with the mathematics of ligand field theory, it is important to comment upon it briefly since we shall be using ligand field stabilization energies (LFSEs) later in this chapter. Ligand field theory is an extension of crystal field theory which is freely parameterized rather than taking a localized field arising from point charge ligands. Ligand field, like crystal field, theory is confined to the role of d orbitals, but unlike the crystal field model, the ligand field approach is not a purely electrostatic model. It is a freely parameterized model, and uses Δ_oct and Racah parameters (to which we return later) which are obtained from electronic spectroscopic (i.e. experimental) data. Most importantly, although (as we showed in the last section) it is possible to approach the bonding in d-block metal complexes by using molecular orbital theory, it is incorrect to state that ligand field theory is simply the application of MO theory.

مواضيع ذات صلة

Crystal field theory

Limitations of VSEPR theory

 Molecular shape and the VSEPR model Valence-shell electron-pair repulsion theory

MO theory: heteronuclear diatomic molecules

The octet rule

The bonding in He2, Li2 and Be2

Molecular orbital theory applied to the bonding in H2

 Homonuclear diatomic molecules: molecular orbital (MO) theory

The valence bond (VB) model applied to F2, O2 and N2

The valence bond (VB) model of bonding in H2

Covalent bond distance, covalent radius and van der Waals radius

Bonding models: an introduction