ISSN:
1572-8854
Keywords:
Solventothermal
;
ternary silver polyselenides
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract Syntheses of the title compounds were achieved from supercritical amines. The single crystal X-ray characterization of both MAgSe4 (M=Rb, Cs) members indicates that they are isostructural. The structure is built from five membered AgSe4 rings that are stitched together through tetrahedrally coordinated Ag(I) ions to form one dimensional chains running parallel to the a-axis. These chains are separated from each other by the alkali metal cations. Crystal data: orthorhombic, P212121, Z = 4. RbAgSe4: a = 5.809(2), b = 8.927(3), c = 13.435(4) Å, U = 698.2(4) Å3, and D c = 4.851 g/cm3. CsAgSe4: a = 5.855(2), b = 9.090(3), c = 13.885(4) Å, U = 739.0(4) Å3, and D c = 5.003 g/cm3. The anionic chain found in the title compounds has been observed previously, and comparisons among these phases show that the silver ion coordination in the chain varies as a function of cation size. Both the title compounds are valence precise and optical diffuse reflectance studies show that they are semiconductors with moderately large band gaps.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1021704302492
Permalink
