J. Phys. Soc. Jpn. 75S (2006) pp. 74-76 |Previous Article| |Next Article| |Table of Contents|
|Full Text PDF: FREE (294K)|
Proc. of 5th Int. Symposium on ASR-WYP-2005 – Advances in the Physics and Chemistry of Actinide Compounds –
Orbital Ordering in Actinide Oxides: New Perspectives on Old Problems
S. B. Wilkins1,
J. A. Paixão2,
R. Caciuffo3,
C. Detlefs1,
J. Rebizant3 and
G. H. Lander3
1European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble CEDEX, France
2Physics Department, University of Coimbra, Coimbra, P-3004-516, Portugal
3European Commission, Joint Research Center, Institute of Transuranium Elements, Postfach 2340, Karlsruhe D-76125, Germany
We report direct experimental evidence for long-range antiferro ordering of the electric-quadrupole moments on the U ions of UO2. Resonant x-ray scattering experiments at the uranium M4 absorption edge show a characteristic dependence in the integrated intensity upon rotation of the crystal around the scattering vector (azimuthal scans) consistent with a transverse ordering of the electric-quadrupole moments. Although quadrupolar order in uranium dioxide was advocated already in the 1960s no experimental evidence for this phenomenon was provided until now.
URL:
http://jpsj.ipap.jp/link?JPSJS/75S/74/
DOI: 10.1143/JPSJS.75S.74
References
- J. A. Paixão et al.:
Phys. Rev. Lett. 89 (2002) 187202[APS].
- R. Caciuffo et al.:
J. Phys.: Condens. Matter 15 (2003) S2287, [IoP STACKS]and references therein.
- S. B. Wilkins et al.:
Phys. Rev. B 70 (2004) 214402[APS].
- S. J. Allen:
Phys. Rev. 166 (1968) 530[APS]; S. J. Allen:
Phys. Rev. 167 (1968) 492[APS].
- J. Faber et al.:
Phys. Rev. Lett. 35 (1975) 1770[APS]; J. Faber et al.:
Phys. Rev. B 14 (1976) 1151[APS].
- J. P. Hill and D. McMorrow: Acta Crystallogr., Sect. A 52 (1996) 236.
- N. Bernhoeft et al.:
Phys. Rev. Lett. 81 (1998) 3419[APS].
- A. Boeuf et al.:
Europhys. Lett. 3 (1987) 221[CrossRef].
