Crystallographic and spectroscopic investigations on nine metal-rare-earth silicates with the apatite structure type
- Autor(en)
- Maria Wierzbicka-Wieczorek, Martin Göckeritz, Uwe Kolitsch, Christoph Lenz, Gerald Giester
- Abstrakt
Nine silicates with the apatite structure type (space group P63/m) contg. both rare-earth elements (REEs: Pr, Nd, Sm, Tb, Ho and Er) and various metals (K, Sr, Ba and Cd) were synthesized by high-temp. flux-growth techniques and characterised by single-crystal X-ray diffraction, SEM, Raman spectroscopy and laser-induced photoluminescence spectroscopy. In all of the compds., the 6h Wyckoff position is predominantly or solely occupied by REE3+ cations, whereas the cations shows a mixed occupancy at the larger, nine-coordinate 4f site with 55-75 % of REE3+ cations and 45-25 % of other metal cations. The O4 ("free" oxygen) site is fully occupied by O2- anions, except for a Ba-Pr member with full occupancy by F- anions. The refined formulas are Cd2Er8(SiO4)6O2, Cd2Tb8(SiO4)6O2, KHo9(SiO4)6O2, KTb9(SiO4)6O2, KSm9(SiO4)6O2, Sr2Nd8(SiO4)6O2, Ba2Nd8(SiO4)6O2, Ba2Sm8(SiO4)6O2 and Ba4Pr6(SiO4)6F2. Changes in the metaprism twist angle (f) and correlations between the unit-cell parameters, av. cationic radii (of M+/M2+-REE3+ pairs) and the chem. of both the synthesized M+/M2+-REE3+ silicate apatites and those reported previously are evaluated. Photoluminescence measurements of undoped samples yielded emission bands in the visible region from green to red; therefore, these compds. are potential candidates for luminescent materials.
- Organisation(en)
- Institut für Mineralogie und Kristallographie
- Externe Organisation(en)
- Naturhistorisches Museum Wien (NHM), Friedrich-Schiller-Universität Jena
- Journal
- European Journal of Inorganic Chemistry
- Band
- 2015
- Seiten
- 948-963
- Anzahl der Seiten
- 16
- ISSN
- 1434-1948
- DOI
- https://doi.org/10.1002/ejic.201403070
- Publikationsdatum
- 01-2015
- Peer-reviewed
- Ja
- ÖFOS 2012
- 104026 Spektroskopie, 104011 Materialchemie, 105113 Kristallographie
- Schlagwörter
- ASJC Scopus Sachgebiete
- Inorganic Chemistry
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/crystallographic-and-spectroscopic-investigations-on-nine-metalrareearth-silicates-with-the-apatite-structure-type(6a3c3f8e-0c59-44f2-bcf7-987d4f771947).html