Weitere Oxochlorotitanate LnTiO3Cl der Seltenen Erden (LnSm?Lu) - Präparation,Kristallstruktur, elektronenmikroskopische Untersuchung |
| |
Authors: | Norbert Hü bner,Katrin Fiedler,Andreas Preuß ,Reginald Gruehn |
| |
Abstract: | New Rare Earth Oxochlorotitanates LnTiO3Cl (Ln?Sm? Lu) - Preparation, Structure and Electron Microscopic Investigations After the preparation of SmTiO3Cl we made the attempt to prepare analogous compounds with the heavier rare earth elements. We present 2 methods to prepare powders of LnTiO3Cl (Ln = Sm? Lu) together with a new method to prepare the rare earth oxychlorides LnOCl (Ln = Tm? Lu). There will be also presented 2 methods to get single crystals of these compounds via chemical vapour transport. The new rare earth oxochlorotitanates LnTiO3Cl (Ln = Eu? Lu) are isotypic to SmTiO3Cl. They crystallize in the monoclinic space group: C2/m (No. 12). The lattice parameters (Å) are between a = 9.716(3), b = 3.942(2), c = 10.100(4) (SmTiO3Cl) and a = 9.748(1), b = 3.8454(5), c = 9.625(2) (LuTiO3Cl), Z = 4. We observed a permanent decay of the cell volume with the decay of the radii of the cations. The structure of EuTiO3Cl and DyTiO3Cl was refined to R = 3.4% and R = 5.8% respectively. The crystal structure which has a certain similarity to brannerite can be described in a simplified way by saying that the rare earth and chlorine particles are located between walls of Ti? O-double-octahedra. |
| |
Keywords: | Rare earth oxychlorides and oxochlorotitanates preparation crystal structure chemical vapour transport electron microscopic investigation |
|
|