Electron diffraction and microscopy study of the structure and microstructure of the hexagonal perovskite Ba3Ti2MnO 9

Christian Maunders, Harold J Whitfield, David G Hay, Joanne Etheridge

Research output: Contribution to journalArticleResearchpeer-review

Abstract

This paper reports a structural and microstructural investigation of the hexagonal perovskite Ba3Ti2MnO9 using electron microscopy and diffraction. Convergent-beam electron diffraction (CBED) revealed the structure has the non-centrosymmetric space group P63mc (186) at room temperature and at ∼ 110 K. Compared with the centrosymmetric parent structure BaTiO3, with space group P63/mmc, this represents a break in mirror symmetry normal to the c axis. This implies the Ti and Mn atoms are ordered on alternate octahedral sites along the 〈0001〉 direction in Ba3Ti2MnO9. Using high-resolution electron microscopy (HREM), we observed occasional 6H/12R interfaces on (0001) planes, however, no antiphase boundaries were observed, as were seen in Ba3Ti2RuO9. Using powder X-ray Rietveld refinement we have measured the lattice parameters from polycrystalline samples to be a = 5.6880 ± 0.0005, c = 13.9223 ± 0.0015 Å at room temperature.
Original languageEnglish
Pages (from-to)390 - 395
Number of pages6
JournalActa Crystallographica. Section B: Structural Science, Crystal Engineering and Materials
Volume63
Issue number3
Publication statusPublished - 2007

Cite this

@article{0900cfe106a84ca49df25087be9dcb71,
title = "Electron diffraction and microscopy study of the structure and microstructure of the hexagonal perovskite Ba3Ti2MnO 9",
abstract = "This paper reports a structural and microstructural investigation of the hexagonal perovskite Ba3Ti2MnO9 using electron microscopy and diffraction. Convergent-beam electron diffraction (CBED) revealed the structure has the non-centrosymmetric space group P63mc (186) at room temperature and at ∼ 110 K. Compared with the centrosymmetric parent structure BaTiO3, with space group P63/mmc, this represents a break in mirror symmetry normal to the c axis. This implies the Ti and Mn atoms are ordered on alternate octahedral sites along the 〈0001〉 direction in Ba3Ti2MnO9. Using high-resolution electron microscopy (HREM), we observed occasional 6H/12R interfaces on (0001) planes, however, no antiphase boundaries were observed, as were seen in Ba3Ti2RuO9. Using powder X-ray Rietveld refinement we have measured the lattice parameters from polycrystalline samples to be a = 5.6880 ± 0.0005, c = 13.9223 ± 0.0015 {\AA} at room temperature.",
author = "Christian Maunders and Whitfield, {Harold J} and Hay, {David G} and Joanne Etheridge",
year = "2007",
language = "English",
volume = "63",
pages = "390 -- 395",
journal = "Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials",
issn = "0108-7681",
publisher = "International Union of Crystallography",
number = "3",

}

Electron diffraction and microscopy study of the structure and microstructure of the hexagonal perovskite Ba3Ti2MnO 9. / Maunders, Christian; Whitfield, Harold J; Hay, David G; Etheridge, Joanne.

In: Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials, Vol. 63, No. 3, 2007, p. 390 - 395.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Electron diffraction and microscopy study of the structure and microstructure of the hexagonal perovskite Ba3Ti2MnO 9

AU - Maunders, Christian

AU - Whitfield, Harold J

AU - Hay, David G

AU - Etheridge, Joanne

PY - 2007

Y1 - 2007

N2 - This paper reports a structural and microstructural investigation of the hexagonal perovskite Ba3Ti2MnO9 using electron microscopy and diffraction. Convergent-beam electron diffraction (CBED) revealed the structure has the non-centrosymmetric space group P63mc (186) at room temperature and at ∼ 110 K. Compared with the centrosymmetric parent structure BaTiO3, with space group P63/mmc, this represents a break in mirror symmetry normal to the c axis. This implies the Ti and Mn atoms are ordered on alternate octahedral sites along the 〈0001〉 direction in Ba3Ti2MnO9. Using high-resolution electron microscopy (HREM), we observed occasional 6H/12R interfaces on (0001) planes, however, no antiphase boundaries were observed, as were seen in Ba3Ti2RuO9. Using powder X-ray Rietveld refinement we have measured the lattice parameters from polycrystalline samples to be a = 5.6880 ± 0.0005, c = 13.9223 ± 0.0015 Å at room temperature.

AB - This paper reports a structural and microstructural investigation of the hexagonal perovskite Ba3Ti2MnO9 using electron microscopy and diffraction. Convergent-beam electron diffraction (CBED) revealed the structure has the non-centrosymmetric space group P63mc (186) at room temperature and at ∼ 110 K. Compared with the centrosymmetric parent structure BaTiO3, with space group P63/mmc, this represents a break in mirror symmetry normal to the c axis. This implies the Ti and Mn atoms are ordered on alternate octahedral sites along the 〈0001〉 direction in Ba3Ti2MnO9. Using high-resolution electron microscopy (HREM), we observed occasional 6H/12R interfaces on (0001) planes, however, no antiphase boundaries were observed, as were seen in Ba3Ti2RuO9. Using powder X-ray Rietveld refinement we have measured the lattice parameters from polycrystalline samples to be a = 5.6880 ± 0.0005, c = 13.9223 ± 0.0015 Å at room temperature.

M3 - Article

VL - 63

SP - 390

EP - 395

JO - Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials

JF - Acta Crystallographica. Section B: Structural Science, Crystal Engineering and Materials

SN - 0108-7681

IS - 3

ER -