Ytterbium divalency and lattice disorder in near-zero thermal expansion YbGaGe

Journal Article · Mon Jan 01 00:00:00 EST 2007 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.75.012301· OSTI ID:20976629

Booth, C H ^[1]; Christianson, A D; Lawrence, J M ^[2]; Pham, L D ^[3]; Lashley, J C ^[4]; Drymiotis, F R ^[5]

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1. Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)
2. Department of Physics and Astronomy, University of California, Irvine, California 92697-4575 (United States)
3. Physics Department, University of California, Davis, California 95616 (United States)
4. Materials Science Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
5. Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634 (United States)

While near-zero thermal expansion (NZTE) in YbGaGe is sensitive to stoichiometry and defect concentration, the NZTE mechanism remains elusive. We present x-ray absorption spectra that show unequivocally that Yb is nearly divalent in YbGaGe and the valence does not change with temperature or with nominally 1% B or 5% C impurities, ruling out a valence-fluctuation mechanism. Moreover, substantial changes occur in the local structure around Yb with B and C inclusion. Together with inelastic neutron scattering measurements, these data indicate a strong tendency for the lattice to disorder, providing a possible explanation for NZTE in YbGaGe.

• OSTI ID: 20976629
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 75, Issue 1; Other Information: DOI: 10.1103/PhysRevB.75.012301; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BORON
CARBON
DEFECTS
GALLIUM COMPOUNDS
IMPURITIES
INELASTIC SCATTERING
NEUTRON DIFFRACTION
NEUTRON REACTIONS
STOICHIOMETRY
THERMAL EXPANSION
VALENCE
X-RAY SPECTRA
YTTERBIUM
YTTERBIUM COMPOUNDS