https://doi.org/10.1007/s100510170178
Phonon dispersion of bcc cerium
1
Physik Department E13, Technische Universität
München, 85747 Garching, Germany
2
Centre de Recherche
sur les Très Basses Températures, 38042 Grenoble, France
3
Institut Laue-Langevin, 38042 Grenoble Cedex, France
Corresponding author: a wpetry@ph.tum.de
Received:
24
January
2001
Published online: 15 June 2001
The phonon dispersion of the high temperature bcc or δ-phase
of cerium has been measured by inelastic neutron
scattering, growing
the single crystals in situ on the spectrometer. The phonon
dispersion shows a
characteristic valley of low energy and strongly
damped phonons along T![$_1[\xi\xi 0]$](/articles/epjb/abs/2001/11/b01036/b01036_tex_eq1.png)
and T![$_1[\xi\xi 2\xi]$](/articles/epjb/abs/2001/11/b01036/b01036_tex_eq2.png)
. From
that the physical origin of the bcc-to-fcc martensitic phase
transition is deduced. A mechanism involving long
wavelength phonons
is proposed.
PACS: 63.20.Dj – Phonon states and bands, normal modes, and phonon dispersion / 64.70.Kb – Solid-solid transitions / 65.40.Gr – Entropy and other thermodynamical quantities
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2001
