[Zurück]

X. Yan, G. Giester, E. Bauer, P. Rogl, S. Paschen:
"Ba-Cu-Si Clathrates: Phase Equilibria and Crystal Chemistry";
Journal of Electronic Materials, 39 (2010), 9; S. 1634 - 1639.

1.-Institute of Solid State Physics, Vienna University of Technology, Wiedner Hauptstr. 8-10,
1040 Vienna, Austria. 2.-Institute of Physical Chemistry, University of Vienna, Wa¨hringerstr.
42, 1090 Vienna, Austria. 3.-Institute of Mineralogy and Crystallography, University of Vienna,
Althanstr. 14, 1090 Vienna, Austria. 4.-e-mail: paschen@ifp.tuwien.ac.at
The formation and crystal chemistry of ternary clathrates in the Ba-Cu-Si
system were investigated on a series of compounds Ba8CuxSi46 x (3 £ x £ 8).
The phase diagram around the clathrate phase was constructed at 800 C,
revealing a homogeneity range from Ba8Cu3.4Si42.6 to Ba8Cu4.8Si41.2. Structural
investigations confirmed that the clathrates in this system crystallize
with cubic primitive symmetry, in the type I clathrate structure (space group
Pm 3n). Single-crystal x-ray diffraction indicates that the Cu atoms partially
substitute for Si atoms on the 6d site; no vacancies are observed.
Key words: Clathrate, phase equilibria, crystal chemistry

http://dx.doi.org/10.1007/s11664-010-1253-x