On the solid solution Sr(1.45–x)CaxSb0.55O3–y

Synthesis, Structural Characterization, and Electrical Properties of (Sr0.5Ca0.5)(Ca0.5Sb0.5)O3−δ Double Perovskites

“…Although in this case the introduction of Ca in the lattice, both in A and B sites, produces a lower lattice parameter than that reported by others. 3,5 The structure shows evidence of B-cation order, as the lattice parameter is doubled and the (111) reflection is clearly indexed in the XRD pattern (Figure 1). 10 B-sites of the structure are occupied 50% by Ca and 50% by Sb; these octahedra show significant differences in the M-O (M = Sb and Ca) bond lengths, and these differences are related with the atomic radius of both atoms, rCa 2þ = 1.14 and rSb 5þ = 0.74, as shown in Figure 3.…”

“…In this case B substitution was only considered in order to increase oxygen vacancies in the sample. Earlier works proposed the addition of Ca to promote the synthesis of double perovskites with formula Sr (1.45− x ) Ca x Sb 0.55 O 3− y , and several compositions were prepared with a cubic symmetry and a cell lattice that decreases when the Ca content increases; nevertheless, the electrical behavior of theses compositions was not tested by the authors. Following these considerations a double perovskite with general formula Sr 0.5 CaSb 0.5 O 3− y has been synthesized and characterized, finding a noticeable amount of oxygen vacancies ( y = 0.25).…”

Phase Chemistry in the Ca‐Mn‐Sb‐O System at 1160–1250 °C

“…The crystal structure of this phase was determined in the space group P12 1 /m1 to be perovskite-like with monoclinic cell parameters: a = 5.6644 ( ) with a cubic structure was produced in air at 1000°C. [39] It was noted that at a large concentration of calcium (x Ͼ 1.1) an impurity phase Ca 6 Sb 2 O 11 appears in the samples. The X-ray diffraction pattern of Ca 7 Sb 2 O 12 contains a number of peaks of small intensity which can't be attributed to one phase from system CaO-Sb 2 O 5 .…”