Year: 2011
Type: article
Abstract: In the Ag–Ba–Si system the clathrate type I solid solution, Ba 8 Ag x Si 46- x , ranges at 800 °C from Ba 8 Ag 4.3 Si 41.7 [ a = 1.04309(3) nm] to Ba 8 Ag 5.4 Si 40.6 [ a = 1.04613(5) nm]. For all clathrate compositions in this homogeneity region (4.3 ≤ x ≤5.4) cubic primitive symmetry with space group P m 3 n was confirmed by X-ray powder diffraction assisted by X-ray single crystal analyses of Ba 8 Ag 4.9 Si 41.1 . Site preference from X-ray refinement reveals that silver atoms preferably occupy the 6d site in random mixture with Si. Ba 2 AgSi 3 (Ba 4 Li 2 Si 6 type, F d d d , a = 0.862, b = 1.493, and c = 1.965 nm), reported by Cardoso et al. , was confirmed. Studies of transport properties for Ba 8 Ag 5 Si 41 evidenced electrons as predominant charge carriers and the closeness of the system to a metal-to-insulator transition.
Institutions: University of Vienna, TU Wien
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2046879853