An inorganic complex of silver (III): K5Ag(IO5OH)2 · 8H2O

The chemical preparation and crystal structure of the trivalent silver salt K₅Ag(IO₅OH)₂ · 8H₂O are described (monoclinic, space group Cc; a = 21.79(4), b = 6.320(3), c = 15.16(3) Å, β = 96.14(4); four formula units per unit cell). The structure is refined until R = 0.033 for 2718 reflections. Isolated Ag(IO₅OH)^5?₂ units occur, which contain trivalent silver ions surrounded by four oxygen atoms from two IO₆ octahedra in rectangular configuration. The differences in the IO bond lengths, as well as the small deviations of the crystal structure from centrosymmetry, are in agreement with an antiperiplanar position of the OH groups in both octahedra.