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Molecular orbital (SCF-Xα-SW) theory of metal-metal charge transfer processes in minerals - II. Application to Fe 2+ --> Ti 4+ charge transfer transitions in oxides and silicates

David M. Sherman
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Abstract

A molecular orbital description, based on Xα-Scattered wave calculations on a (FeTiO 10 ) 14− cluster, is given for Fe 2+ → Ti 4+ charge transfer transitions in minerals. The calculated energy for the lowest Fe 2+ → Ti 4+ metal-metal charge transfer transition is 18040 cm −1 in reasonable agreement with energies observed in the optical spectra of Fe-Ti oxides and silicates. As in the case of Fe 2+ → Fe 3+ charge transfer in mixed-valence iron oxides and silicates, Fe 2+ → Ti 4+ charge transfer is associated with Fe-Ti bonding across shared polyhedral edges. Such bonding results from the overlap of the Fe( t 2 g ) and Ti( t 2 g ) 3 d orbitals.

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David M. Sherman. 1987. Molecular orbital (SCF-Xα-SW) theory of metal-metal charge transfer processes in minerals - II. Application to Fe 2+ --> Ti 4+ charge transfer transitions in oxides and silicates. https://doi.org/10.1007/bf00309811

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