title: The unique bis-(disulfato)-aurate anion [Au(S2O7)2](-): synthesis and characterization of Li[Au(S2O7)2] and Na[Au(S2O7)2)].
abstract: The reaction of Au(OH)(3) and oleum (65% SO(3)) in the presence of M(2)SO(4) (M = Li, Na) afforded yellow single crystals of Li[Au(S(2)O(7))(2)] (triclinic, P ̅1, Z = 1, a = 532.20(3), b = 649.69(4), c = 836.72(5) pm, α = 107.982(2)°, β = 90.171(2)°, γ = 102.583(2)°, V = 267.80(3) Å(3)) and Na[Au(S(2)O(7))(2)] (monoclinic, P2(1)/n, Z = 2, a = 533.31(3), b = 1193.38(7), c = 907.67(5) pm, β = 98.548(3)°, V = 571.26(6) Å(3)). Both compounds exhibit the unprecedented [Au(S(2)O(7))(2)](-) anion in which a square planar coordination of the central gold atom is achieved by the chelating attachment of two disulfate groups. The disulfates were characterized by means of IR spectroscopy and DTA/TG measurements. For both compounds, the decomposition occurs via several steps and is finished at about 450 °C at the stage of elemental gold and the sulfates M(2)SO(4) (M = Li, Na), as revealed by X-ray powder diffraction of the residues.
authors.affiliation: Institute of Pure and Applied Chemistry, Carl von Ossietzky University of Oldenburg, Carl-von-Ossietzky-Str. 9-11, 26129 Oldenburg, Germany. christian.logemann@uni-oldenburg.de
authors.forename: Christian
authors.initials: C
authors.lastname: Logemann
authors.forename: Mathias S
authors.initials: MS
authors.lastname: Wickleder