First Anhydrous Gold Perchlorato Complex: ClO 2 Au(ClO 4 ) 4 . Synthesis and Molecular and Crystal Structure Analysis
Résumé
Chlorine trioxide, Cl2O6, reacts with Au metal, AuCl3, or HAuCl4·nH2O to yield the well-defined chloryl salt, ClO2Au(ClO4)4. The crystal and molecular structure of ClO2Au(ClO4)4 was solved by a Rietveld analysis of powder X-ray diffraction data. The salt crystallizes in a monoclinic cell, space group C2/c, with cell parameters a = 15.074(5), b = 5.2944(2), and c = 22.2020(2) Å and β = 128.325(2)°. The structure displays discrete ClO2+ ions lying in channels formed by Au(ClO4)4- stacks. Au is located in a distorted square planar environment: Au−O = 1.87 and 2.06 Å. [ClO4] groups are monodentate with ClOb = 1.53 and ClOt = 1.39 Å (mean distances; Ob, oxygen bonded to Au; Ot, free terminal oxygen). A full vibrational study of the Au(ClO4)4- anion is supported by DFT calculations.