Synthetic, structural and thermal studies of Ag(I)-XeF_2 complex salts

摘要

The Ag(I)-XeF_2 complex salt, [Ag(XeF_2)_2]PF_6, was obtained by the reaction of XeF_2 and AgPF_6 in anhydrous hydrogen fluoride (aHF). The compound crystallizes in the space group I4c2 with a=8.467(3)A, b=12.745(3)A, V=913.69(5)A~3, Z=4, isostructural with the previously reported [Ag(XeF_2)_2]AsF_6 salt. A two-dimensional NaCl-type arrangement of AgPF_6 is observed in [Ag(XeF_2)_2]PF_6. Four XeF_2 molecules (Xe-F=1.983(8) or 2.040(8)A, F-Xe-F=175.7(16) deg) inserted between the AgPF_6 sheets and four PF_6~- anions around the Ag~+ cation form a cubic coordination sphere of F atoms around the cation. Syntheses of the XeF_2 complex salts of AgSbF_6, AgNbF_6 and AgTaF_6 all failed under the same conditions.