Magnetic properties of coordination compounds

Ciofini, I. and Daul, C. A. 2003. DFT Calculations of Molecular Magnetic Properties of Coordination Compounds , Coord. Chem. Rev.. 238, 187. 

Use crystal field theory to interpret the magnetic properties of coordination compounds in terms of the electron configurations of their central ions (Section 8.4, Problems 21-25). 

We explore how crystal-field theory allows us to explain some of the interesting spectral and magnetic properties of coordination compounds. 

However, the valence bond theory approach to transition metals has severe limitations. It fails to account for the absorption spectra and magnetic properties of coordination compounds. These and other properties are more satisfactorily explained by crystal field theory or ligand field theory. 

As discussed previously, the magnitude of the crystal field splitting energy largely determines the number of unpaired electrons in a given compound. This in turn, as we see in this section, has a direct bearing on the magnetic properties of coordination compounds. 

We see, then, that the magnetic properties of coordination compounds are consistent with CFT. Furthermore, these properties can be used to substantiate the spectrochemical series of ligands. 

Confirmation of CFT comes from a consideration of the magnetic properties of coordination compounds. Molar susceptibilities, derived from measurements on a Guoy balance, can be related to the magnetic moment of the complex. A comparison of this experimentally derived magnetic moment with spin-only moments yields a measure of the number of unpaired electrons in the compound. The results derived from a consideration of magnetic properties are consistent with CFT. 

Magnetic Properties of Coordination Compounds and Crystal Field Theory... 

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