[Zurück]

A. Grytsiv, P. Rogl, St Berger, C. Paul, H. Michor, E. Bauer, G. Hilscher, C. Godart, P. Knoll, M. Musso, W. Lottermoser, A. Saccone, R. Ferro, H. Noel:
"A novel skutterudite phase in the Ni-Sb-Sn system: phase equilibria and physical properties";
Journal of Physics: Condensed Matter, 14 (2002), S. 7071 - 7090.

A novel ternary phase, SnyNi4Sb12−xSnx, has been characterized and found to
exhibit a wide range of homogeneity (at 250 ◦C, 2.4 x 5.6, 0 y 0.31;
at 350 ◦C, 2.7 x 5.0, 0 y 0.27). SnyNi4Sb12−xSnx crystallizes
in a skutterudite-based structure in which Sn atoms are found to occupy
two crystallographically inequivalent sites: (a) Sn and Sb atoms randomly
share the 24g site; and (b) a small fraction of Sn atoms occupy the 2a
(0, 0, 0) position, with an anomalously large isotropic atomic displacement
parameter. Eu0.8Ni4Sb5.8Sn6.2, Yb0.6Ni4Sb6.7Sn5.3 and Ni4As9.1Ge2.9 are
isotypic skutterudites. Depending on the particular composition, metallic as
well as semiconducting states appear. The crossover from semiconducting to
metallic behaviour is discussed in terms of a temperature-dependent carrier
concentration employing a simple model density of states with the Fermi
energy slightly below a narrow energy gap. This model accounts for the
peculiar temperature-dependent electrical resistivity. These skutterudites are
characterized by a number of lattice vibrations, which were elucidated by
Raman measurements and compared to the specific heat data. The Eucontaining
compound exhibits long-rangemagnetic order at Tmag ≈ 6K, arising
from the Eu2+ ground state.

http://stacks.iop.org/0953-8984/14/7071