| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1505702 | Solid State Sciences | 2011 | 11 Pages |
Single-phase samples of Ln2−xCaxCoO4+δ (Ln = Pr3+ − Gd3+) around x∼1 have been prepared. For the first time, the phase field for these compounds has been defined using powder X-ray diffraction and a very narrow solid solution was observed. Under our synthetic conditions, the K2NiF4 structure was not formed for the large La3+ ion, or for compositions containing the smaller rare earths ions ( Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Phase field for Ln2−xCaxCoO4+δ (Ln = Pr3+ − Gd3+) determined. ► Average cobalt oxidation states between ∼3.2+ and ∼3.3+. ► Tetragonal to orthorhombic transition upon cooling and with decreasing ionic radius. ► Paramagnetic with weak antiferromagnetic interactions. ► Co3+ in low-spin state.
