Crystal field theoiy

In broad terms, there are two very different theories which have been used to interpret the properties of transition-metal compounds MO theory and crystal field theoiy. ... 

A satisfactory theory of bonding in coordination compounds must account for properties such as color and magnetism, as well as stereochemistiy and bond strength. No single theoiy as yet does all this for us. Rather, several different approaches have been applied to transition metal complexes. We will consider only one of them here—crystal field theoiy— because it accounts for both the color and magnetic properties of many coordination compounds. 

We will begin our discussion of crystal field theoiy with the most straightforward case— namely, complex ions with octahedral geometiy. Then we will see how it is applied to tetrahedral and square-planar complexes. 

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