Nano‐Domain Twin Structure Formed by Phase Transition in New Perovskite Oxide (Sr_0.67Sm_0.33)(Mn_0.33Ti_0.67)O₃

Abstract

A new perovskite oxide, (Sr0.67Sm0.33)(Mn0.33Ti0.67)O3, was synthesized at 1573 K in an Ar flow. The structure of the oxide was determined to be orthorhombic with the space group of Pnma using X‐ray diffraction and electron diffraction. High‐resolution transmission electron microscope (HRTEM) images of the oxide revealed that nano‐domain structures were formed by twinning due to a phase transition. This is the first time that phase transition of the oxide has been observed in situ using a heating stage in a TEM. The high‐temperature phase possessed an orthorhombic structure with the space group of Imma, which appeared above 723 K.

Phase formation, structural and microstructural characterization of novel oxynitride–perovskites synthesized by thermal ammonolysis of (Ca,Ba)MoO4 and (Ca,Ba)MoO3

“…Formation of twin domains of these types has been reported earlier for a number of distorted perovskite-type oxides with similar lattice parameters (in our case the mismatch for CaMoO 3 between a and b is 2.3%, whereas for CaMoO 1.7(1) N 1.3(1) the mismatch is 0.9%) [34][35][36][37].…”

Phase transitions in a perovskite thin film studied by environmental in-situ heating nano-beam electron diffraction

“…1(b)-(d). This reflects a nanotwinned state of the film as it is often observed in orthorhombic systems [19,20]. Interestingly, there is no unique relation between orientation and bright and dark appearance in the ADF-STEM image in Fig.…”

Phase Transitions in a Perovskite Thin Film Studied by Environmental In Situ Heating Nano‐Beam Electron Diffraction

“…This reflects a nanotwinned state of the film as it is often observed in orthorhombic systems. [ 47,48 ]…”

“…This reflects a nanotwinned state of the film as it is often observed in orthorhombic systems. [47,48] The temperature dependent lattice parameters obtained in the TEM and averaged over the upper half of the scanning field in Figure 2 zone axis orientation, respectively. While in the former case a PCMO(0 1 2 0) superreflection emerges at 800 K, the PCMO(101) reflection vanishes in the latter.…”