Morin transition of shock-modified hematite
Journal Article
·
· Phys. Rev. B: Condens. Matter; (United States)
Hematite (..cap alpha..-Fe/sub 2/O/sub 3/) powder compacts have been subjected to controlled, quantitative high-pressure shock loading at peak pressures from 8 to 27 GPa and preserved for postshock analysis. Analysis of broadened x-ray line profiles shows a reduction of average crystallite size to about 60 nm and retained lattice strains near 0.1% in the recovered samples. Moessbauer and magnetization measurements show drastically altered behavior of the Morin transition: large fractions of the Fe sites do not exhibit the transition, and those that do have a significantly reduced transition temperature and an increased thermal hysteresis. The Moessbauer quadrupole splitting is sensitive to the shock compression conditions and provides evidence for a less than 90/sup 0/ spin flip at the Morin transition for the higher-pressure shock loading. A small fraction of the hematite is converted to magnetite (Fe/sub 3/O/sub 4/) under the most extreme shock condition examined. In some cases the observed effects can be attributed to either the reduced crystallite size or the large defect density associated with the residual strain.
- Research Organization:
- Physics Department, Colorado School of Mines, Golden, Colorado 80401
- OSTI ID:
- 5587088
- Journal Information:
- Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 34:3; ISSN PRBMD
- Country of Publication:
- United States
- Language:
- English
Similar Records
Shock-modified transition metal ferrites
Spin orientation, structure, morphology, and magnetic properties of hematite nanoparticles
Crystallite size effect in the selective oxidation of butene to butadiene on iron oxide. 1. Moessbauer, X-ray, and magnetization characterization of the catalysts
Technical Report
·
Mon Jun 01 00:00:00 EDT 1987
·
OSTI ID:6359892
Spin orientation, structure, morphology, and magnetic properties of hematite nanoparticles
Journal Article
·
Thu May 07 00:00:00 EDT 2015
· Journal of Applied Physics
·
OSTI ID:22403022
Crystallite size effect in the selective oxidation of butene to butadiene on iron oxide. 1. Moessbauer, X-ray, and magnetization characterization of the catalysts
Journal Article
·
Sat Dec 31 23:00:00 EST 1983
· J. Phys. Chem.; (United States)
·
OSTI ID:5827374
Related Subjects
36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ANTIFERROMAGNETISM
CHALCOGENIDES
COHERENT SCATTERING
COMPACTS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DATA
DIFFRACTION
EXPERIMENTAL DATA
HEMATITE
HYSTERESIS
INFORMATION
IRON COMPOUNDS
IRON ORES
IRON OXIDES
LINE WIDTHS
MAGNETISM
MAGNETIZATION
MINERALS
MOESSBAUER EFFECT
NUMERICAL DATA
ORES
ORTHORHOMBIC LATTICES
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
POWDERS
SCATTERING
SHOCK WAVES
TRANSITION ELEMENT COMPOUNDS
VERY HIGH PRESSURE
X-RAY DIFFRACTION
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ANTIFERROMAGNETISM
CHALCOGENIDES
COHERENT SCATTERING
COMPACTS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DATA
DIFFRACTION
EXPERIMENTAL DATA
HEMATITE
HYSTERESIS
INFORMATION
IRON COMPOUNDS
IRON ORES
IRON OXIDES
LINE WIDTHS
MAGNETISM
MAGNETIZATION
MINERALS
MOESSBAUER EFFECT
NUMERICAL DATA
ORES
ORTHORHOMBIC LATTICES
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
POWDERS
SCATTERING
SHOCK WAVES
TRANSITION ELEMENT COMPOUNDS
VERY HIGH PRESSURE
X-RAY DIFFRACTION