Gold heptafluoride is a gold(V) compound with the empirical formula AuF₇. The synthesis of this compound was first reported in 1986. However, current calculations suggest that the structure of the synthesized molecule was actually a

difluorine Fluorine is a chemical element with the symbol F and atomic number 9. It is the lightest halogen and exists at standard conditions as a highly toxic, pale yellow diatomic gas. As the most electronegative reactive element, it is extremely reactive, ...

ligand on a gold pentafluoride core, AuF₅·F₂. That would make it the first

difluorine complex A difluorine complex is a molecular complex involving a difluorine molecule (F2) and another molecule. The first example was gold heptafluoride (AuF7). Instead of being a gold(VII) compound, AuF7 is an adduct of gold pentafluoride (AuF5) and F2. ...

and the first compound containing a fluorine atom with an

oxidation state In chemistry, the oxidation state, or oxidation number, is the hypothetical charge of an atom if all of its bonds to different atoms were fully ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. C ...

of zero. The gold(V)–difluorine complex is calculated to be 205

kJ/mol The joule per mole (symbol: J·mol−1 or J/mol) is the unit of energy per amount of substance in the International System of Units (SI), such that energy is measured in joules, and the amount of substance is measured in moles. It is also an S ...

more stable than gold(VII) fluoride. The

vibrational frequency A molecular vibration is a periodic motion of the atoms of a molecule relative to each other, such that the center of mass of the molecule remains unchanged. The typical vibrational frequencies range from less than 1013 Hz to approximately 1014 ...

at 734 cm⁻¹ is the hallmark of the end-on coordinated difluorine molecule.

References

Fluorides Metal halides Gold–halogen compounds Substances discovered in the 1980s {{Inorganic-compound-stub