Nd2(WO4)3

نویسندگان

  • Matthias Weil
  • Berthold Stöger
  • Lyubomir Aleksandrov
چکیده

The title compound, dineodymium(III) tris-[tungstate(VI)], is a member of the Eu(2)(WO(4))(3) structure family and crystallizes isotypically with other rare earth tungstates and molybdates of this formula type. The structure is a derivative of the scheelite (CaWO(4)) structure and can be considered as an ordered defect variant with a threefold scheelite supercell and one rare earth (RE) site unoccupied. The Nd(3+) cations are coordinated by eight O atoms in form of a distorted bicapped trigonal prism. The two unique W cations are tetra-hedrally surrounded by O atoms. One WO(4) tetra-hedron has 2 symmetry and is relatively undistorted whereas the other tetra-hedron differs considerably from an ideal geometry. This is caused by an additional remote O atom at a distance of 2.149 (4) Å. The resulting WO(4 + 1) polyhedra form W(2)O(8) dimers through edge-sharing. Together with the WO(4) and NdO(8) units, the three-dimensional set-up is accomplished.

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Preparation of Camera-ready Typescript:

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عنوان ژورنال:

دوره 65  شماره 

صفحات  -

تاریخ انتشار 2009