Crystal structure of the
ternary compound Dy3Ga2.54Sn2.46
Chem.
Met. Alloys 5
(2012) 160-165
https://doi.org/10.30970/cma5.0225
Vitaliia FEDYNA, Yaroslav TOKAYCHUK,
Roman GLADYSHEVSKII
The crystal structure of the new ternary
compound Dy3Ga2.54(5)Sn2.46(5)
belongs to the Pu3Pd5 structure type (Pearson symbol oS32,
space group Cmcm,
a = 9.7300(3), b = 7.7081(2), c = 9.7925(3) Å). The atoms of the p-elements are distributed over three Wyckoff positions with a tendency towards
ordering: two sites for Ga and one site for Sn (ideal composition Dy3Ga3Sn2).
They form isolated empty square-pyramidal clusters. The structure can also be
decomposed into two kinds of layer. At z
≈ 0 and z ≈ ½ Dy (site Dy1) and Ga (site M2 = 0.81(3)Ga2
+ 0.19(3)Sn2) atoms form slightly puckered deformed NaCl-type
layers. At z = ¼ and z = ¾ Dy
(site Dy2), Ga (M3
= 0.74(3)Ga3 + 0.26(3)Sn3) and Sn
(M1 = 0.09(4)Ga1 + 0.91(4)Sn1) atoms
form flat deformed LiFeO2-type layers (the LiFeO2 type is
a ternary ordered derivative of the binary NaCl
type). The structure type Pu3Pd5 belongs to the family of
deformation variants of the structure type Rh5Ge3.
Content of the unit cell and square
pyramidal arachno-type clusters in the structure of
Dy3Ga2.54Sn2.46.
Keywords
Dysprosium
/ Gallium / Tin / Intermetallic compound / X-ray
powder diffraction / Crystal
structure