Crystal chemical peculiarities of the intermetallic compound Pr(Ni0.2Al0.3Ge0.5)1.8

1Muts, NM, Akselrud, LG, 1Gladyshevskii, RE
1Ivan Franko National University of Lviv
Dopov. Nac. akad. nauk Ukr. 2017, 11:67-75
Section: Chemistry
Language: Ukrainian

The crystal structure of the Pr(Ni0.2Al0.3Ge0.5)1.8 compound was refined based on X-ray single-crystal diffraction data: modulated structure (basic structure type AlB2) superspace group PA2mm (p00,0q0)m0m with modulation wave vectors p = 0.1540(1), q = 0.3384(1), a = 4.221(2) Å, b = 4.255(2) Å, c = 7.370(3) Å. The structural modulations are induced by the ordering of different sorts of atoms; the modulations of the substitution and displacement of atoms from the ideal positions were observed; the ordering of small-size atoms has own symmetry, which does not correspond to the symmetry of the parent AlB2-type structure.

Keywords: crystal structure, germanide, X-ray diffraction
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