Thermodynamic behaviour of Ni

Chapter 7 discusses some of the thermodynamic properties of transition metal compounds and minerals that are influenced by crystal field effects. The characteristic double-humped curves in plots of thermodynamic data for suites of transition metal-bearing phases originate from contributions from the crystal field stabilization energy. However, these CFSE s, important as they are for explaining differences between individual cations, make up only a small fraction of the total energy of a transition metal compound. In the absence of spectroscopic data, CFSE s could be evaluated from the double-humped curves of thermodynamic data for isochemical compounds of the first transition series. 

Fe/Mg ratios in coexisting silicates. The CFSE s acquired by Fe2+ ions in ferromagnesian silicates obtained from spectral measurements may be used to explain Fe/Mg ratios in coexisting silicate minerals. The orders of decreasing CFSE between igneous mineral assemblages 

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