English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Structural and Magnetic Phase Transitions in the AnBnO3n-2 Anion-Deficient Perovskites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16

MPS-Authors
/persons/resource/persons126888

Tsirlin,  A. A.
Chemical Metal Science, Max Planck Institute for Chemical Physics of Solids, Max Planck Society;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available
Citation

Abakumov, A. M., Batuk, M., Tsirlin, A. A., Tyablikov, O. A., Sheptyakov, D. V., Filimonov, D. S., et al. (2013). Structural and Magnetic Phase Transitions in the AnBnO3n-2 Anion-Deficient Perovskites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16. Inorganic Chemistry, 52(14), 7834-7843. doi:10.1021/ic3026667.


Cite as: https://hdl.handle.net/11858/00-001M-0000-0015-1E90-B
Abstract
Novel anion-deficient perovskite-based ferrites Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 were synthesized by solid-state reaction in air. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 belong to the perovskite-based A(n)B(n)O(3n-2) homologous series with n = 5 and 6, respectively, with a unit cell related to the perovskite subcell a(p) as a(p)root 2 x a(p) x na(p) root 2. Their structures are derived from the perovsldte one by slicing it with 1/2[110](p)((1) over bar 01)(p) crystallographic shear (CS) planes. The CS operation results in ((1) over bar 01)(p)-shaped perovsldte blocks with a thickness of (n - 2) FeO6 octahedra connected to each other through double chains of edge-sharing FeO5 distorted tetragonal pyramids which can adopt two distinct mirror-related configurations. Ordering of chains with a different configuration provides an extra level of structure complexity. Above T approximate to 750 K for Pb2Ba2BiFe5O13 and T approximate to 400 K for Pb1.5Ba2.5Bi2Fe6O16 the chains have a disordered arrangement. On cooling, a second-order structural phase transition to the ordered state occurs in both compounds. Symmetry changes upon phase transition are analyzed using a combination of superspace crystallography and group theory approach. Correlations between the chain ordering pattern and octahedral tilting in the perovskite blocks are discussed. Pb2Ba2BiFe5O13 and Pb1.5Ba2.5Bi2Fe6O16 undergo a transition into an antiferromagnetically (AFM) ordered state, which is characterized by a G-type AFM ordering of the Fe magnetic moments within the perovsldte blocks. The AFM perovsldte blocks are stacked along the CS planes producing alternating FM and AFM-aligned Fe-Fe pairs. In spite of the apparent frustration of the magnetic coupling between the perovskite blocks, all n = 4, 5, 6 A(n)Fe(n)O3(n-2) (A = Pb, Bi, Ba) feature robust antiferromagnetism with similar Neel temperatures of 623-632 K.