Pyrosulfate
In chemistry, disulfate or pyrosulfate is the anion with the molecular formula. Disulfate is the IUPAC name.
It has a dichromate-like structure and can be visualised as two corner-sharing SO4 tetrahedra, with a bridging oxygen atom.
In this anion, sulfur has an oxidation state of +6. Disulfate is the conjugate base of the hydrogen disulfate ion, which in turn is the conjugate base of disulfuric acid.