Crystals 2011, 1(4), 244-253; doi:10.3390/cryst1040244
Article

Defect Scheelite-Type Lanthanoid(III) Ortho-Oxomolybdates(VI) Ln0.667[MoO4] (Ln = Ce, Pr, Nd, and Sm) and Their Relationship to Zircon and the NaTl-Type Structure

email, email, email and * email
Received: 14 October 2011; in revised form: 22 November 2011 / Accepted: 30 November 2011 / Published: 5 December 2011
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract: The rare-earth metal(III) ortho-oxomolybdates with the formula Ln0.667[MoO4] (Ln = Ce, Pr, Nd, and Sm) and defect scheelite-type structure crystallize in the tetragonal space group I41/a (a = 533–525, c = 1183–1158 pm) with four formula units per unit cell. The Ln3+ cations at Wyckoff position 4b exhibit a coordination sphere of eight oxygen atoms in the shape of a trigonal dodecahedron. The same site symmetry (..) is observed for the tetrahedral oxomolybdate(VI) entities [MoO4]2–, since their central Mo6+ cation is situated at the 4a position. Due to this equal site multiplicity, the lanthanoid(III) cations have to be statistically under-occupied to maintain electroneutrality, thus a defect scheelite structure emerges. The partial structure of both the Ln3+ cations and the [MoO4]2– anions (if shrunk to their centers of gravity) can be best described as distorted diamond-like arrangements. Therefore, these two interpenetrating partial structures exhibit a similar setup as found in the zircon-type as well as in the NaTl-type structure.
Keywords: lanthanoids; ortho-oxomolybdates; scheelite-type; crystal structure
PDF Full-text Download PDF Full-Text [1632 KB, uploaded 5 December 2011 11:41 CET]

Export to BibTeX |
EndNote


MDPI and ACS Style

Schustereit, T.; Müller, S.L.; Schleid, T.; Hartenbach, I. Defect Scheelite-Type Lanthanoid(III) Ortho-Oxomolybdates(VI) Ln0.667[MoO4] (Ln = Ce, Pr, Nd, and Sm) and Their Relationship to Zircon and the NaTl-Type Structure. Crystals 2011, 1, 244-253.

AMA Style

Schustereit T, Müller SL, Schleid T, Hartenbach I. Defect Scheelite-Type Lanthanoid(III) Ortho-Oxomolybdates(VI) Ln0.667[MoO4] (Ln = Ce, Pr, Nd, and Sm) and Their Relationship to Zircon and the NaTl-Type Structure. Crystals. 2011; 1(4):244-253.

Chicago/Turabian Style

Schustereit, Tanja; Müller, Sabine L.; Schleid, Thomas; Hartenbach, Ingo. 2011. "Defect Scheelite-Type Lanthanoid(III) Ortho-Oxomolybdates(VI) Ln0.667[MoO4] (Ln = Ce, Pr, Nd, and Sm) and Their Relationship to Zircon and the NaTl-Type Structure." Crystals 1, no. 4: 244-253.

Crystals EISSN 2073-4352 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert