| Autor: |
Wolska, E., Stempin, K., Krasnowska-Hobbs, O. |
| Zdroj: |
Solid State Ionics; 1997, Vol. 101 Issue: 1 p527-531, 5p |
| Abstrakt: |
Solid solutions formed between the cubic spinel LiMn 2 O 4 and the ordered spinel Li 0.5 Fe 2.5 O 4 have been investigated by X-ray powder diffraction, infrared spectroscopy and magnetic techniques. The series shows a spinel structure with the unit-cell constant increasing from a = 8.209 A˚ to a = 8.335 A˚, with the increasing Fe/(Fe + Mn) ratio. For 0 ≤ Fe/(Fe + Mn) ≤ 0.6 the cubic spinel structures (space group Fd3m) were formed, while in samples with higher Fe content the ordering of lithium ions leads to the lowering of symmetry (space group P4 1 32). The measurements of integrated intensities of X-ray reflections show the distribution of Li ions in both octahedral and tetrahedral cationic positions of spinel lattice, although the end-members of the series, LiMn 2 O 4 and LiFe 5 O 8 , contain Li coordinated tetrahedrally and octahedrally, respectively. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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