| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1602211 | Intermetallics | 2007 | 6 Pages |
The two new ternary scandium tellurides SrSc2Te4 and BaSc2Te4 were prepared by heating the elements at temperatures between 800 °C and 900 °C under vacuum. Both compounds crystallize in the CaFe2O4 type, space group Pnma, Z = 4, with lattice dimensions of a = 13.1795(17) Å, b = 4.2323(7) Å, c = 15.367(2) Å, V = 857.2(2) Å3 for SrSc2Te4, and a = 13.292(2) Å, b = 4.2694(7) Å, c = 15.523(3) Å, V = 880.9(2) Å3 for BaSc2Te4. The structures comprise a three-dimensional network of edge- and corner-sharing ScTe6 octahedra. The Sr and Ba cations are located in linear channels, surrounded by eight Te atoms forming bicapped trigonal prisms. SrSc2Te4 and BaSc2Te4 are electron-precise materials exhibiting common oxidation states, Sr2+, Ba2+, Sc3+, and Te2−. We calculated the band gaps to be 0.1 eV for SrSc2Te4 and 0.2 eV for BaSc2Te4. At room temperature, both materials exhibit a high Seebeck coefficient and low electrical conductivity.
