The fluorosulfates or fluorosulfonates are a set of salts of

fluorosulfuric acid Fluorosulfuric acid (IUPAC name: sulfurofluoridic acid) is the inorganic compound with the chemical formula HSO3F. It is one of the strongest acids commercially available. It is a tetrahedral molecule and is closely related to sulfuric acid, H2SO4 ...

with an ion formula SO₃F⁻. The fluorosulfate anion can be treated as though it were a

hydrogen sulfate The sulfate or sulphate ion is a polyatomic ion, polyatomic anion with the empirical formula . Salts, acid derivatives, and peroxides of sulfate are widely used in industry. Sulfates occur widely in everyday life. Sulfates are salt (chemistry), ...

anion with hydroxyl substituted by fluorine. The fluorosulfate ion has a low propensity to form complexes with metal cations. Since fluorine is similar in size to oxygen, the fluorosulfate ion is roughly

tetrahedral In geometry, a tetrahedron (plural: tetrahedra or tetrahedrons), also known as a triangular pyramid, is a polyhedron composed of four triangular faces, six straight edges, and four vertex corners. The tetrahedron is the simplest of all the o ...

and forms salts similar to those of the

perchlorate A perchlorate is a chemical compound containing the perchlorate ion, . The majority of perchlorates are commercially produced salts. They are mainly used as oxidizers for pyrotechnic devices and to control static electricity in food packaging. Per ...

ion. It is

isoelectronic Isoelectronicity is a phenomenon observed when two or more molecules have the same structure (positions and connectivities among atoms) and the same electronic configurations, but differ by what specific elements are at certain locations in the ...

with hydrogen sulfate, . When an organic group is substituted for the anions, organic fluorosulfonates are formed. In solution the fluorosulfate anion is completely ionised. The volume of the ions is 47.8 cm³/mol. Most metal ions, and quaternary ammonium ions, can form fluorosulfate salts. Different ways to make these salts include treating a metal chloride with anhydrous fluorosulfuric acid, which releases hydrogen chloride gas. Double decomposition methods utilising a metal sulfate with barium fluorosulfate, or a metal chloride with silver fluorosulfate, leave the metal salt in solution. The fluorosulfate anion is weakly coordinating, and is difficult to oxidise. It is important historically as a model

weakly coordinating anion Anions that interact weakly with cations are termed non-coordinating anions, although a more accurate term is weakly coordinating anion. Non-coordinating anions are useful in studying the reactivity of electrophilic cations. They are commonly found ...

. However, by the twenty-first century fluorosulfate was superseded in this use, in particular by BARF. Many pseudobinary fluorosulfate salts are known. They are called pseudobinary, because although there is one other element, there are four kinds of atoms. Nonmetal pseudobinary fluorosulfates are known including those of halogens and xenon. Some pseudoternary fluorosulfates exist including Cs b(SO₃F)₆ Cs u(SO₃F)₄ Cs₂ t(SO₃F)₆ref name="mich16"/> Related ionic compounds are the fluoroselenites SeO₃F⁻ and the fluorosulfites SO₂F⁻. The sulfate fluorides are distinct, as they contain fluoride ions without a bond to the sulfate groups. One fluorosulfate containing mineral called

reederite-(Y) Reederite-(Y) is a rare mineral with the formula . It is the only known mineral with fluorosulfate ( fluorosulfonate). "REE" in the formula stands for rare earth elements other than yttrium, that is mostly cerium, with traces of neodymium, dysprosi ...

exists. It is a

mixed anion compound Mixed anion compounds, heteroanionic materials or mixed anion materials are chemical compounds containing cations and more than one kind of anion. The compounds contain a single phase, rather than just a mixture. Use in materials science By havin ...

that also contains carbonate and chloride.

Compounds

References

{{Reflist Fluorine compounds Sulfur oxyanions