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Silver zinc zirconium fluoride; Fluorine; X-ray diffraction; Silver dimers; Magnetic properties
Abstract:
Deep blue-violet colored powder samples of Ag(2)ZnZr(2)F(14) were synthesized by heating Zn(NO(3))(2)center dot 4H(2)O, Ag and ZrOCl(2)center dot 8H(2)O at 300 degrees C under fluorine atmosphere. The crystal structure of Ag(2)ZnZr(2)F(14) was refined from X-ray powder diffraction data using the Rietveld method (C2/m, a = 9.0206(1) angstrom, b = 6.6373(1) angstrom, c = 9.0563(1) angstrom, beta = 90.44(1)degrees, Z = 2). The structure is derived from the isotypic Ag(3)Zr(2)F(14) by replacing only one of the two crystallographi-cally different Ag(2+) ions with Zn(2+) ions, thus leading to discrete Ag(2)F(7) dimers. These dimers are connected via nearly linear Ag-F center dot center dot center dot F-Ag bridges with short F center dot center dot center dot F distances of 2.33 angstrom to form two-legged ladders. Magnetic susceptibility measurements and density functional calculations show that the two Ag(2+) ions in each Ag(2)F(7) dimer are strongly coupled antiferromagnetically.
