Crystal Field Theory (CFT), An Introduction.

In the ionic CFT, it is assumed that the ions are simple point charges. When applied to alkali metal ions containing a symmetric sphere of charge, calculations of bond energies are generally quite successful. The approach taken uses classical potential energy equations that take into account the attractive and repulsive interactions between charged particles (that is, Coulomb's Law interactions).

The bond energy between the charges is proportional to q₁ * q₂/r

where q₁ and q₂ are the charges of the interacting ions and r is the distance separating them. This leads to the correct prediction that large cations of low charge, such as K⁺ and Na⁺, should form few coordination compounds.

For transition metal cations that contain varying numbers of d electrons in orbitals that are NOT spherically symmetric, however, the situation is quite different. The shape and occupation of these d-orbitals then becomes important in an accurate description of the bond energy and properties of the transition metal compound.

To be able to understand and use CFT then, it is essential to have a clear picture of the shapes (angular dependence functions) of the d-orbitals.



To continue click on the link below:

http://wwwchem.uwimona.edu.jm/courses/CFT.html