Pressure-induced strain transition in NiF/sub 2/

Journal Article · Wed Mar 01 04:00:00 EST 1978 · Phys. Rev., B; (United States)

DOI:https://doi.org/10.1103/PhysRevB.17.2212· OSTI ID:5095245

Jorgensen, J D; Worlton, T G; Jamieson, J C

We report time-of-flight neutron powder diffraction measurements which give the first direct evidence that NiF/sub 2/ undergoes a pressure-induced, continuous phase transition from tetragonal P4/sub 2//mnm (rutile) to orthorhombic Pnnm at 18.3 +- 1 kbar. The square of the strain (b - a) varies linearly with pressure above the transition and extrapolates to zero at the transition pressure. Measured atomic positions and thermal displacements show that motion of the F atoms is responsible for the transition.

• Research Organization: Argonne National Laboratory, Argonne, Illinois 60439
• OSTI ID: 5095245
• Journal Information: Phys. Rev., B; (United States), Journal Name: Phys. Rev., B; (United States) Vol. 17:5; ISSN PLRBA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
COHERENT SCATTERING
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
DIFFRACTION
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
NEUTRON DIFFRACTION
NICKEL COMPOUNDS
NICKEL FLUORIDES
ORTHORHOMBIC LATTICES
PHASE TRANSFORMATIONS
PRESSURE DEPENDENCE
SCATTERING
STRAINS
TETRAGONAL LATTICES
TRANSITION ELEMENT COMPOUNDS