Structural Features of Ag[AuF4] and Ag[AuF6] and the Stuctural Relationship of Ag[AgF4]2 and Au[AuF4]2 to Ag[AuF4]2

Synchrotron radiation X-ray powder diffraction data (SPDD) have been obtained for Ag[AgF4]2, Au[AuF4]2, Ag[AuF4], and Ag[AuF6]. Ag[AgF4]2 and Au[AuF4]2 are isostructural with Ag[AuF4]2, space group (SG) P21/n, Z = 2, with the following: for Ag[AgF4]2 a = 5.04664(8), b = 11.0542(2), c = 5.44914(9) Å, β = 97.170(2)°; for Au[AuF4]2 a = 5.203(2), b = 11.186(3), c = 5.531(2) Å, β = 90.55(2)°. The structure of Ag[AgF4]2 was refined successfully (SPDD) applying the Rietveld method, yielding the following interatomic distances (Å): AgII−F = 2.056(12), 2.200(13), 2.558(13); AgIII−F = two at 1.846(12), others = 1.887(12), 1.909(13), 2.786(12), 2.796(12), 2.855(12). AgAuF4, like other AA‘F4 salts (A = Na−Rb; A‘ = Ag, Au), crystallizes in the KBrF4 structure type, SG I4/mcm (140), Z = 4 with a = 5.79109(6), c = 10.81676(7) Å. SPDD gave (in Å) four AuIII−F = 1.89(1) and eight AgI−F = 2.577(7). SPDD for AgAuF6 confirmed that it has the LiSbF6 structure, SG R3̄, Z = 3, with a = 5.2840(2), c = 15.0451(6) Å.