Gold(II) sulfate is the chemical compound with the formula AuSO4 or more correctly Au2(SO4)2. This compound was previously thought to be a mixed-valent compound as AuIAuIII(SO4)2. But later, it was shown that it contained the diatomic cation, Au4+ 2 which made it the first simple inorganic gold(II) compound. The bond distance between the gold atoms in the diatomic cation is 249 pm.[1][2]