THE PRESSURE-DEPENDENCE OF THE TA(1)[110] PHONON FREQUENCIES IN THE ORDERED INVAR ALLOY FE3PT AT PRESSURES UP TO 7 GPA

Authors
SCHWOERERBOHNING M KLOTZ S BESSON JM BURKEL E BRADEN M PINTSCHOVIUS L
Citation
M. Schwoererbohning et al., THE PRESSURE-DEPENDENCE OF THE TA(1)[110] PHONON FREQUENCIES IN THE ORDERED INVAR ALLOY FE3PT AT PRESSURES UP TO 7 GPA, Europhysics letters, 33(9), 1996, pp. 679-682
Citations number
8
Categorie Soggetti
Physics
Journal title
Europhysics letters → ACNP
ISSN journal
02955075
Volume
33
Issue
9
Year of publication
1996
Pages
679 - 682
Database
ISI
SICI code
0295-5075(1996)33:9<679:TPOTTP>2.0.ZU;2-7
Abstract
The pressure dependence of the TA(1)[110] phonon frequencies in ordere d Fe3Pt was studied by inelastic neutron scattering up to 7 GPa. Very large frequency shifts (similar to 50%) were observed in this pressure range. We found that the mode Gruneisen parameters remain very large (similar to 8) for pressures exceeding the critical pressure of about 3 GPa, which drives ordered Fe3Pt from a high-spin to a low-spin state . This indicates that the unusually large Gruneisen parameters are pro bably not a magnetoelastic effect, but rather have to be associated wi th the martensitic instability.