Origin of forbidden reflections in multiferroic Ba2CoGe2O7 by neutron diffraction: Symmetry lowering or Renninger effect?

Andrew Sazonov, Martin Meven, Georg Roth, Robert Georgii, I. Kézsmárki, Vilmos Kocsis, Yusuke Tokunaga, Yasujiro Taguchi, Yoshinori Tokura, Vladimir Hutanu

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

For a symmetry-consistent theoretical description of the multiferroic phase of Ba2CoGe2O7 a precise knowledge of its crystal structure is a prerequisite. In a previous synchrotron X-ray diffraction experiment on multiferroic Ba2CoGe2O7 at room temperature, forbidden reflections were found that favour the tetragonal-to-orthorhombic symmetry lowering of the compound [Hutanu, Sazonov, Murakawa, Tokura, Náfrádi & Chernyshov (2011), Phys. Rev. B, 84, 212101]. Here, the results are reported of room-temperature single-crystal diffraction studies with both hot and cold neutrons to differentiate between genuine symmetry lowering and multiple diffraction (the Renninger effect). A comparison of the experimental multiple diffraction patterns with simulated ones rules out symmetry lowering. Thus, the structural model based on the tetragonal space group was selected to describe the Ba2CoGe2O7 symmetry at room temperature. The precise structural parameters from neutron diffraction at 300K are presented and compared with the previous X-ray diffraction results.

Original languageEnglish
Pages (from-to)556-560
Number of pages5
JournalJournal of Applied Crystallography
Volume49
DOIs
Publication statusPublished - 2016

Fingerprint

Neutron Diffraction
Neutron diffraction
X-Ray Diffraction
Temperature
Diffraction
X ray diffraction
Synchrotrons
Structural Models
Neutrons
Diffraction patterns
Crystal structure
Single crystals
Experiments

Keywords

  • multiferroic melilite
  • multiple diffraction
  • Renninger effect
  • single-crystal neutron diffraction
  • UMWEG

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)

Cite this

Origin of forbidden reflections in multiferroic Ba2CoGe2O7 by neutron diffraction : Symmetry lowering or Renninger effect? / Sazonov, Andrew; Meven, Martin; Roth, Georg; Georgii, Robert; Kézsmárki, I.; Kocsis, Vilmos; Tokunaga, Yusuke; Taguchi, Yasujiro; Tokura, Yoshinori; Hutanu, Vladimir.

In: Journal of Applied Crystallography, Vol. 49, 2016, p. 556-560.

Research output: Contribution to journalArticle

Sazonov, Andrew ; Meven, Martin ; Roth, Georg ; Georgii, Robert ; Kézsmárki, I. ; Kocsis, Vilmos ; Tokunaga, Yusuke ; Taguchi, Yasujiro ; Tokura, Yoshinori ; Hutanu, Vladimir. / Origin of forbidden reflections in multiferroic Ba2CoGe2O7 by neutron diffraction : Symmetry lowering or Renninger effect?. In: Journal of Applied Crystallography. 2016 ; Vol. 49. pp. 556-560.
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AU - Hutanu, Vladimir

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