Synthesis and Structure Determination of Sm3NbSe3O4

✍ Scribed by A. Meerschaut; C. Boyer; A. Lafond; L. Cario; J. Rouxel

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 344 KB
• Volume: 137
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1997.7731

✦ Synopsis

Sm 3 NbSe 3 O 4 has been synthesized and its structure determined. The following crystal data were obtained: M r ‫؍‬ 844.84 g • mol ؊1 , orthorhombic, Pnma, a ‫؍‬ 6.8943(4) A > , b ‫؍‬ 7.7529(8) A > , c ‫؍‬ 14.7644(12) A > , V ‫؍‬ 789.2(1) A > 3 , Z ‫؍‬ 4, D x ‫؍‬ 7.111 g • cm ؊3 , MoK , ‫؍‬ 0.71073 A > , ‫؍‬ 372 cm ؊1 , F(000) ‫؍‬ 1444, T ‫؍‬ 295 K, R ‫؍‬ 0.035 for 1466 unique reflections with F o > 4 (F o ), 62 variables, GoF ‫؍‬ 0.818. The structure of Sm 3 NbSe 3 O 4 was determined by single-crystal X-ray diffraction. Two distinct types of polyhedra can be distinguished: a very distorted one with eight surrounding atoms (four O and four Se atoms) around Sm1 and Nb, and a bicapped trigonal prismatic one around Sm2. The crystal structure of this new compound can be described on the basis of corrugated planes perpendicular to the c axis. These planes are built up from edge-sharing trigonal prismatic polyhedra (Sm2); connection between successive planes is achieved through the distorted polyhedra which surround atoms Sm1 and Nb.