Chemical Properties
White Fine Powder
Physical properties
Barium fluoride (BaF2), also known as barium(II)
fluoride, is a solid which can also be a transparent
crystal. Its molecular weight is 175.34 g/mol. It occurs
in nature as the mineral “Frankdicksonite”. It occurs as
a white powder with a melting point of 1290 and a boiling point of 2259°C. It is slightly soluble in water
(0.159 at 0.0°C and 0.162 g/100 ml of water at 20°C). The solid generally assumes the fluorite structure, but
when subjected to high pressure, changes to the PbCl2
structure. In the vapor phase, the BaF2 molecule is
nonlinear with an F–Ba–F angle of approximately 108°C.
Uses
As a flux and opacifier in vitreous enamels; in the manufacture of carbon brushes for DC motors and generators; in heat-treating metals; in embalming; in glass manufacture.
Application
Barium fluoride is used as the transmission window in λ: 150 nm–10 mm and as the Reststrahlen filter in λ: 30–60 mm.
Production Methods
A single crystal of Barium fluoride is grown from the melt solution by the Kyropoulos method and the Stockbarger method.
Flammability and Explosibility
Nonflammable
Solubility in water
Barium fluoride is soluble in water with the solubility of 0.17 g/100 g H2O (10 ℃). It is also soluble in acid and ammonium chloride.
Purification Methods
Wash it well with distilled H2O and dry it in a vacuum. Its solubility in H2O is 1.6g (10o), 1.6g (20o) and 1.62g (30o) per L, and is soluble in mineral acids and aqueous NH4Cl. It may be stored in glass bottles. [Kwasnik in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I p 234 1963.]
Structure and conformation
The space lattice of Barium fluoride (BaF2) belongs to the cubic system, and its calcium fluoride structure has a lattice constant of a=0.6187 nm and Ba–F=0.268 nm.
