Abstract
The compound CsAgSb4S7 has been synthesized by the reaction of the elements in a Cs2S3 flux at 773 K. The compound crystallizes in a new structure type with eight formula units in space group C2/c of the monoclinic system in a cell at 153 K of dimensions a = 26.127(2) Å, b = 8.8599(7) Å, c = 12.100(1) Å, β = 97.650(1)°, and V = 2776.0(4) Å3. The structure contains two-dimensional ∞2[AgSb4S7] layers separated by Cs atoms. Each ∞2[AgSb 4S7] layer is built from edge-sharing one-dimensional ∞1[AgS3] and ∞ 1[Sb4S7] chains. Each Ag atom is tetrahedrally coordinated to four S atoms. Each Sb3+ center is pyramidally coordinated to three S atoms to form an SbS3 group. CsAgSb 4S7 is insulating with an optical band gap of 2.04eV. Extended Hückel calculations indicate that the band gap in CsAgSb 4S7 is dominated by the Sb 5s and S 3p states above and below the Fermi level.
Original language | English (US) |
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Pages (from-to) | 212-217 |
Number of pages | 6 |
Journal | Journal of Solid State Chemistry |
Volume | 178 |
Issue number | 1 |
DOIs | |
State | Published - Jan 1 2005 |
Keywords
- Cesium silver antimony sulfide
- Crystal structure
- Electronic structure
- Optical absorption spectrum
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Ceramics and Composites
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Inorganic Chemistry
- Materials Chemistry