- published: 23 Jun 2015
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Gold heptafluoride is a gold(V) compound with the empirical formula AuF7. The synthesis of this compound was first reported in 1986. Current calculations proved that it may be the first difluorine complex, AuF5·F2. The gold(V) difluorine complex is calculated to be 205 kJ/mol more stable than gold(VII) fluoride. The vibrational frequency at 734 cm-1 is the symbol of the end-on coordinated difluorine molecule.
Gold ( /ˈɡoʊld/) is a chemical element with the symbol Au (from Latin: aurum "gold") and an atomic number of 79. Gold is a dense, soft, shiny, malleable and ductile metal. Pure gold has a bright yellow color and luster traditionally considered attractive, which it maintains without oxidizing in air or water. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements solid under standard conditions. The metal therefore occurs often in free elemental (native) form, as nuggets or grains in rocks, in veins and in alluvial deposits. Less commonly, it occurs in minerals as gold compounds, usually with tellurium.
Gold resists attacks by individual acids, but it can be dissolved by the aqua regia (nitro-hydrochloric acid), so named because it dissolves gold. Gold also dissolves in alkaline solutions of cyanide, which have been used in mining. Gold dissolves in mercury, forming amalgam alloys. Gold is insoluble in nitric acid, which dissolves silver and base metals, a property that has long been used to confirm the presence of gold in items, giving rise to the term the acid test.