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0
–700
–1400
20 26 32 38 44 50 56 62 68 74
2θ, deg
Fig. 7. The XRD pattern for Sr Gd Fe O refined by
2 7 – δ
1.1
1.9
the Rietveld method.
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CONCLUSIONS
The formation of perovskite-like solid solutions
n + 1BnO3n + 1 of three types (n = 1, 2, ∞) in the
Sm2O3–CaO–MO and Ln2O3–SrO–MO systems (Ln
= Sm, Gd; M = Fe, Co) with varying of degrees of sub-
stitution in the A sublattice was established by XRD. A
crystal structure for all single-phase oxides was deter-
mined and the unit cell parameters and the atomic coor-
dinates were refined. It is shown that the unit cell param-
eters and the unit cell volume of solid solutions decrease
with the rise in concentration of lanthanide ions.
A
FUNDING
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This work was supported by the Russian Federation
Ministry of Science and Higher Education (state research
target, project no. 4.2288.2017/PCh).
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work, K., and Withers, R., Orthorhombic superstruc-
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INORGANIC MATERIALS
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2019