title: Role of the lattice in the gamma-->alpha phase transition of Ce: a high-pressure neutron and x-ray diffraction study.
abstract: The temperature and pressure dependence of the thermal displacements and lattice parameters were obtained across the gamma-->alpha phase transition of Ce using high-pressure, high-resolution neutron and synchrotron x-ray powder diffraction. The estimated vibrational entropy change per atom in the gamma-->alpha phase transition, DeltaS(gamma-alpha)(vib) approximately (0.75+/-0.15)k(B), is about half of the total entropy change. The bulk modulus follows a power-law pressure dependence that is well described using the framework of electron-phonon coupling. These results clearly demonstrate the importance of lattice vibrations, in addition to the spin and charge degrees of freedom, for a complete description of the gamma-->alpha phase transition in elemental Ce.
authors.affiliation: Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA. jeong@lanl.gov
authors.forename: I-K
authors.initials: IK
authors.lastname: Jeong
authors.forename: T W
authors.initials: TW
authors.lastname: Darling
authors.forename: M J
authors.initials: MJ
authors.lastname: Graf
authors.forename: Th
authors.initials: T
authors.lastname: Proffen
authors.forename: R H
authors.initials: RH
authors.lastname: Heffner
authors.forename: Yongjae
authors.initials: Y
authors.lastname: Lee
authors.forename: T
authors.initials: T
authors.lastname: Vogt
authors.forename: J D
authors.initials: JD
authors.lastname: Jorgensen