Determination of the charge-ordered phases in LuFe2O4

DOI: 10.1209/0295-5075/107/47002

Authors: Sara Lafuerza Bielsa (ESRF-The European Synchrotron; CSIC-Universidad de Zaragoza) , Gloria Subias-Peruga (CSIC-Universidad de Zaragoza) , Javier Blasco (CSIC-Universidad de Zaragoza) , Joaquin Garcia (CSIC-Universidad de Zaragoza) , Gareth Nisbet (Diamond Light Source) , Kazimierz Conder (Paul Scherrer Institut - 5232 Villigen PSI) , Ekaterina Pomjakushina (Paul Scherrer Institut - 5232 Villigen PSI)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Epl (europhysics Letters) , VOL 107 (4)

State: Published (Approved)
Published: August 2014

Abstract: High-resolution synchrotron powder diffraction and Fe K-edge x-ray resonant scattering (RXS) have been combined to determine both the magnitude and sequence of the Fe charge segregation in LuFe2O4. Two phases with different charge disproportionation were found below the so-called charge ordering transition temperature TCO ≈ 320K. The crystal structure between 320K and 200K shows a C2/m symmetry where four non-equivalent iron sites with different valences were determined (Fe2.77+, Fe2.63+, Fe2.36+ and Fe2.26+). Below 200K the structure further changes to the P¯1 symmetry and six crystallographic sites for the iron atoms were found. The simplest valence distribution corresponds to a tri-modal one, where the six Fe atoms are grouped in couples with three valences Fe2.8+, Fe2.5+ and Fe2.2+. Both polar and anti-polar charge sequences have been discarded.

Diamond Keywords: Ferroelectricity

Subject Areas: Physics, Materials


Instruments: I16-Materials and Magnetism

Other Facilities: ID31 at ESRF

Added On: 04/09/2014 10:51

Discipline Tags:

Quantum Materials Physics Magnetism Materials Science

Technical Tags:

Scattering Resonant Soft X-ray Scattering (RSXS)