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Updated: May 26, 2026

Synthesis and Characterization of Functionalized Metal-organic Frameworks
Published on: September 5, 2014
Na(1.5)Ag(1.5)MO3F3 (M = Mo, W): an ordered oxyfluoride derivative of the LiNbO3 structure
Allyson M Fry1, Harry A Seibel, Indunil N Lokuhewa
1Department of Chemistry, The Ohio State University, Columbus, Ohio 43210-1185, USA.
Abstract:
Na(1.5)Ag(1.5)MoO(3)F(3) and Na(1.5)Ag(1.5)WO(3)F(3) have been synthesized by solid state reactions and structurally characterized using synchrotron X-ray and neutron powder diffraction. Unlike the vast majority of salts containing [MO(3)F(3)](3-) anions (M = Mo, W) the oxyfluoride groups in Na(1.5)Ag(1.5)MoO(3)F(3) and Na(1.5)Ag(1.5)WO(3)F(3) are orientationally ordered, so that the Na(+) ions are coordinated by fluorine and the Ag(+) ions by oxygen. The resulting structure type, which has not previously been reported, is related to the LiNbO(3) structure, but the combination of Na/Ag ordering and orientational ordering of the [MO(3)F(3)](3-) anions produces a supercell that doubles the c-axis and changes the space group symmetry from R3 to R3. The use of hard (Na(+)) and soft (Ag(+)) cations to direct the orientational ordering of polar oxyfluoride building units provides a new approach to the design of polar materials.
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