| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1332787 | Journal of Solid State Chemistry | 2006 | 5 Pages |
Single crystals of the new binaries CeTe1.90 and SmTe1.80 have been obtained. CeTe1.90 was synthesized at 1023 K from the reaction of Ce, TeO2, and Te with the use of a CsCl flux. It crystallizes in the tetragonal space group P42/n with 20 formula units in a cell of dimensions at 153 K of a=10.0261(5)a=10.0261(5), c=18.1336(12)Å, V=1822.84(18)Å3. It is isostructural with the LnSe1.9 polyselenides (Ln=La, Ce, Pr) and with SmS1.90. SmTe1.80 was synthesized at 1223 K from the reaction of Sm and Te in a KBr flux. SmTe1.80 crystallizes in a new structural type in the tetragonal space group P4/n with 20 formula units in a cell of dimensions at 153 K of a=9.7026(4)a=9.7026(4), c=18.0072(14)Å, V=1695.21(14)Å3. Both of these layered structures, which may be derived from the ZrSiS structure type, consist of double layers of [LnTe] polyhedra separated by planar Te nets that contain vacancies. In these nets the shortest Te–Te distances are 2.9194(5), 3.1204(5), and 3.3324(6) Å in CeTe1.90 and 2.878(1), 2.9932(3), and 3.2114(7) Å in SmTe1.80. Neither a simple delineation of the Te–Te bonding nor an assignment of individual formal oxidation states is possible in either of these compounds if one takes strict account of the Te–Te distances.
Graphical abstractA Te net in SmTe1.80.Figure optionsDownload full-size imageDownload as PowerPoint slide
