| Autor: |
Levytskyy V; Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla & Mefodiya street 6, 79005 Lviv, Ukraine., Babizhetskyy V; Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla & Mefodiya street 6, 79005 Lviv, Ukraine., Kotur B; Department of Inorganic Chemistry, Ivan Franko National University of Lviv, Kyryla & Mefodiya street 6, 79005 Lviv, Ukraine., Smetana V; 344 Spedding Hall, Ames Laboratory, Ames, IA 50011-3020, USA. |
| Jazyk: |
angličtina |
| Zdroj: |
Acta crystallographica. Section E, Structure reports online [Acta Crystallogr Sect E Struct Rep Online] 2014 Jul 05; Vol. 70 (Pt 8), pp. i42. Date of Electronic Publication: 2014 Jul 05 (Print Publication: 2014). |
| DOI: |
10.1107/S1600536814015384 |
| Abstrakt: |
The crystal structure of the title compound, Tb2Ni7, was redetermined from single-crystal X-ray diffraction data. In comparison with previous studies based on powder X-ray diffraction data [Lemaire et al. (1967). C. R. Acad. Sci. Ser. B, 265, 1280-1282; Lemaire & Paccard (1969). Bull. Soc. Fr. Mineral. Cristallogr. 92, 9-16; Buschow & van der Goot (1970). J. Less-Common Met. 22, 419-428], the present redetermination affords refined coordinates and anisotropic displacement parameters for all atoms. A partial occupation for one Tb atom results in the non-stoichiometric composition Tb1.962 (4)Ni7. The title compound adopts the Ce2Ni7 structure type and can also be derived from the CaCu5 structure type as an inter-growth structure. The asymmetric unit contains two Tb sites (both site symmetries 3m.) and five Ni sites (.m., mm2, 3m., 3m., -3m.). The two different coordination polyhedra of Tb are a Frank-Kasper polyhedron formed by four Tb and 12 Ni atoms and a pseudo Frank-Kasper polyhedron formed by two Tb and 18 Ni atoms. The four different coordination polyhedra of Ni are Frank-Kasper icosa-hedra formed by five Tb and seven Ni atoms, four Tb and eight Ni atoms, three Tb and nine Ni atoms, and six Tb and six Ni atoms, respectively. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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