Volodymyr BABIZHETSKYY, Bogdan KOTUR
Ivan Franko National University of Lviv, Kyryla and Mefodiya Str. 6, 79005 Lviv, Ukraine e-mail: volodymyr.babizhetskyy@lnu.edu.ua
DOI: https://doi.org/10.37827/ntsh.chem.2021.66.107
NON-STOICHIOMETRY OF GdFe2Si2: A SINGLE CRYSTAL STUDY
The title compound was prepared from the elements by arc-melting under argon followed by annealing in silica tubes at 800 °C for one month. The crystal structure of GdFe2Si2 was investigated by means of X-ray study of two single crystals, as well as powder X-ray diffraction phase and structural analyses and energy dispersive X-ray spectroscopy of four polycrystal samples. GdFe2Si2 crystallizes in the CeGa2Al2 structure type, space group I4/mmm, a = 3.938(1), c = 10.080(3) Å, Z = 2, R1 = 0.024, wR2 = 0.039 for 78 unique reflections with Io > 2σ(Io) and 9 parameters. For the compound with smaller unit cell volume the Fe position is not fully occupied and the refinement results for a composition GdFe1.92Si2 is in agreement with the data of chemical analysis: space group I4/mmm, a = 3.9467(7), c = 9.710(2) Å, Z = 2, R1 = 0.031, wR2 = 0.063 for 102 unique reflections with Io > 2σ(Io) and 10 parameters. Narrow homogeneity range GdFe2-xSi2 (0 ≤ x ≤ 0.08) for the compound was detected.
Keywords: ternary silicides, rare earth metals, single crystal, crystal structure.
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How to Cite
BABIZHETSKYY V., KOTUR B. NON-STOICHIOMETRY OF GdFe2Si2: A SINGLE CRYSTAL STUDY. Proc. Shevchenko Sci. Soc. Chem. Sci. 2021 Vol. LXVI. P. 107-116.