K2TaF7

K2TaF7, also known as potassium heptafluorotantalate(V), is an inorganic compound with the chemical formula K2TaF7. It is a white crystalline solid and is a salt of potassium and the heptafluorotantalate anion. This compound is typically prepared by the reaction of tantalum(V) fluoride with potassium fluoride. It is a member of the alkali metal heptafluorometallate(V) family, which includes similar compounds of other Group 5 metals like niobium and antimony.

K2TaF7 is known for its relatively high melting point and stability. It is sparingly soluble in water, but its solubility can increase in the presence of excess fluoride ions. The structure of K2TaF7 consists of potassium cations and discrete [TaF7]2- anions. The heptafluorotantalate anion has a pentagonal bipyramidal coordination geometry around the tantalum atom.

This compound finds applications primarily in materials science and research. It can be used as a precursor in the synthesis of other tantalum-containing compounds, including tantalum oxides and nitrides, which are utilized in electronics and ceramics. K2TaF7 also plays a role in the extraction and purification of tantalum metal. Its study contributes to understanding the coordination chemistry of tantalum and the properties of fluorinated inorganic salts.