| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1507158 | Solid State Sciences | 2006 | 7 Pages |
The crystal structure of the new compound Co7(TeO3)4Br6 is described together with the magnetic properties. The new compound crystallizes in the monoclinic space group C2/c with the unit cell parameters a=20.6532(5) Åa=20.6532(5) Å, b=8.6533(2) Åb=8.6533(2) Å, c=14.7262(5) Åc=14.7262(5) Å, β=124.897(3)°β=124.897(3)°, Z=4Z=4. The crystal structure was solved from single crystal data, R=0.0242R=0.0242. The structure can be considered as layered and the building units are [CoO4Br2] and [CoO2Br4] octahedra and [TeO3E] tetrahedra, E being the 5s2 lone pair on the Te(IV) ions. The magnetic properties of the compound are characterised by antiferromagnetic correlations at high temperatures, strong deviation from the Curie–Weiss behaviour in a broad intermediate temperature range and long range magnetic ordering setting-in at low temperatures. Magnetic ordering takes place in stages, being represented by two susceptibility anomalies, at TN=33 KTN=33 K and TC=27 KTC=27 K. The magnetic transition at TCTC is ferromagnetic (or ferrimagnetic) in character.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide
