The trans isomer of the organogold(III) difluoride complex [PPh₄][(CF₃)₃AuF₂] has been obtained in a stereoselective way and in excellent yield by reaction of [PPh₄][CF₃AuCF₃] with XeF₂ under mild conditions. The compound is both thermally stable and reactive. Thus, the fluoride ligands are stereospecifically replaced by any heavier halide or by cyanide, the latter affording [PPh₄][trans-(CF₃)₃Au(CN)₃]. The organogold fluoride complexes [CF₃AuF_x]^- (x = 1, 2, 3) have been experimentally detected to arise upon collision-induced dissociation of the [trans-(CF₃)₃AuF₂]^- anion in the gas phase. Their structures have been calculated by DFT methods. In the isomeric forms identified for the open-shell species [CF₃AuF₂]^-, the spin density residing on the metal center is found to strongly depend on the precise stereochemistry. Finally, and based on experimental crystallographic evidence, it is concluded that Au(III) and Ag(III) have similar covalent radii, at least in their most common square-planar geometry.