Site symmetry of tetrahedral (A) and octahedral (B) sites of the spinel structures in the solid solulion of Fe
3O
4-Mn
3O
4 and Fe
3O4-Fe
2TiO
4 varies microscopically with their cation distribution. Variations of the local distortion due to the Jahn-Teller distortion of Mn
3+ in B site affect the electric field gradient of cations. This gradient is related to the nuclear quadrupole splitting in the Mossbauer spectra. The above variations also affect lattice vibration, which is recognized by the far-infrared absorption spectra. Factors obtained from these spectra shift continuously over the whole range of Fe
3O
4-Mn
3O
4 solid solution.
Atomic positional disorder and electron localization by the Jahn-Teller effect give rise to the local distorion, which affects anisotropic temperature factors. From this point of view, X-ray crystal structure analysis can be used for the observation of local displacement of atomic position resulting from the variation of local site symmetry. The structure analysis of Fe
3O
4-Fe
2TiO
4 solid solution shows that temperature factors of oxygen considerably varies with the degree of substitution and displacement of oxygen atom results in the local distortion of polyhedra.
The observations of these different types of methods give a consistent result for the local site symmetry of the solid solutions.
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