As-As dimerization, Fermi surfaces and the anomalous electrical transport properties of UAsSe and ThAsSe

Journal Article · Sat Jul 15 00:00:00 EDT 2006 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2006.04.016· OSTI ID:20905366

Withers, Ray L ^[1]; Prodan, Albert ^[2]; Midgley, P A ^[3]; Schoenes, J ^[4]; Vincent, R ^[5]

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1. Research School of Chemistry, Australian National University, Canberra, ACT 0200 (Australia)
2. Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia)
3. Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ (United Kingdom)
4. Institut fuer Physik der Kondensierten Materie, Technical University Braunschweig, D-38106 Braunschweig (Germany)
5. H.H. Wills Physics Laboratory, University of Bristol, Bristol, BS8 1TL (United Kingdom)

A temperature dependent electron diffraction study has been carried out on UAsSe to search for evidence of As-As dimerization at low temperature. A highly structured characteristic diffuse intensity distribution, closely related to that recently reported for ThAsSe, has been observed at low temperature and interpreted in terms of a gradual charge density wave type phase transition upon lowering of temperature involving disordered As-As dimerization within (001) planes. Plausible models of the proposed As-As dimerization have been obtained using a group theoretical approach. Electronic band structure calculations of ThAsSe and UAsSe have been used to search for potential Fermi surface nesting wave-vectors. The results are in good agreement with the experimentally observed diffuse intensity distributions in both cases. - Graphical abstract: A typical <001> zone axis EDP of UAsSe taken at {approx}80-90 K. In addition to the strong Bragg reflections of the underlying P4/nmm average structure, note the presence of a highly structured characteristic diffuse intensity distribution arising from disordered As-As dimerization.

• OSTI ID: 20905366
• Journal Information: Journal of Solid State Chemistry, Vol. 179, Issue 7; Other Information: DOI: 10.1016/j.jssc.2006.04.016; PII: S0022-4596(06)00238-6; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ARSENIC
ARSENIC ALLOYS
BRAGG REFLECTION
CHARGE DENSITY
CHARGED-PARTICLE TRANSPORT
DIMERIZATION
ELECTRON DIFFRACTION
FERMI LEVEL
KONDO EFFECT
PHASE TRANSFORMATIONS
SELENIUM ALLOYS
TEMPERATURE DEPENDENCE
THORIUM ALLOYS
URANIUM ALLOYS