GENERATION OF AU2+ IONS IN THE SOLID-STATE OR IN FLUOROSULFURIC ACID-SOLUTION AND THEIR IDENTIFICATION BY ESR

The partial pyrolysis of gold(III) fluorosulfate, Au(SO3F)3, at temperatures below 145-degrees-C allows the generation of Au2+ defects in the solid residue by reductive elimination of SO3F. radicals. Solvated Au2+ is obtained by the reduction of Au(SO3F)3 in HSO3F solution by gold powder at 65-degrees-C. Both systems are studied by ESR and identical high g(iso) values of g = 2.360 are found. Hyperfine splitting due to Au-197, I = 3/2, is observed in frozen solutions of Au2+(solv). Pyrolysis of Br3[Au(SO3F)4] also gives partly pyrolyzed Au(SO3F)3, with a sufficiently high Au2+ ion concentration, to allow a magnetic susceptibility study between 100 and 295 K.