A series of polyether [CH3O(CH2CH2O)(m)CH3, with m = 2 (diglyme), 3 (triglyme), 4 (tetraglyme)] mono- or hemiadducts of hexafluoropentanedionatosilver(I) have been synthesized and in selected cases structurally characterized. Decomposition of [Ag(hfa)(diglyme)](2) (hfa = hexafluoropentanedionato) in air affords a mixture of products including crystals of [Ag-2(hfa)(O2CCF3)(diglyme)(2)]. The structure of [Ag(hfa)(diglyme)](2) consists of two silver cations which are bridged by four oxygens from two hfa ligands; each Ag(I) ion is also coordinated to a chelating diglyme molecule. In comparison, ligation of a longer polyether chain results in a monomeric species [Ag(hfa)(tetraglyme)]. The compounds are soluble in a range of solvents including supercritical carbon dioxide (scCO(2)). Crystal data for [Ag(hfa)(diglyme)](2) (150 K) : a = 21.376(3) Angstrom, b = 8.4143(17) Angstrom, c = 21.067(3) Angstrom, beta = 124.05(1)degrees, monoclinic space group C2/c; Z = 8. Crystal data for [Ag-2(hfa)(O2CCF3)(diglyme)(2)] (150 K) : a = 9.0945(12) Angstrom, b = 9.4110(13) Angstrom, c = 17.803(2) Angstrom, alpha = 96.109(14)degrees, beta = 101.649(13)degrees, gamma = 105.06-(2)degrees, triclinic space group P (1) over bar; Z = 2. Crystal data for [Ag(hfa)(tetraglyme)] (150 K) : a = 14.152(3) Angstrom, b = 16.996(3) Angstrom, c = 8.620(2) Angstrom, beta = 106.99(2)degrees, monoclinic space group P2(1)/c; Z = 4.