BaF2

BaF2, or barium difluoride, is an inorganic salt consisting of barium cations (Ba2+) and fluoride anions (F−). It forms white, crystalline solids that crystallize in the fluorite structure, in which each Ba2+ is coordinated by eight fluoride ions and each F− is coordinated by four Ba2+ ions. The compound is chemically stable under normal conditions and is commonly produced synthetically for industrial use.

BaF2 has a high melting point and is relatively insoluble in water, making it a hard, brittle solid at room temperature. It is more reactive with acids, which release hydrogen fluoride and other products. In air and moisture-free environments it remains stable, but it can be attacked by strong acids or fluorinating agents.

The material is valued for its optical and radiation-detection properties. BaF2 transmits ultraviolet light and is used as a UV-transparent window and lens material in specialized optical systems. It is also employed as a scintillator in radiation detectors, where it can emit light in response to ionizing radiation, contributing to imaging and spectroscopy applications.

BaF2 is not known as a natural mineral and is normally produced by industrial synthesis. Common preparation routes include precipitation from aqueous solutions of barium salts with fluoride sources or direct fluorination of barium compounds. Safety considerations are important: although relatively insoluble, barium compounds can be toxic, and fluoride release under acidic conditions requires appropriate handling and disposal.