Characteristic

Lanthanum hexaboride (LaB₆, also called lanthanum boride and LaB) is an inorganic chemical, a boride of lanthanum. It is a refractory ceramic material that has a melting point of 2210 °C, and is insoluble in water and hydrochloric acid.

Chemical formula：LaB₆

Molar mass： 203.78 g/mol

Appearance： intense purple violet

Density： 4.72 g/cm³

Melting point： 2,210 °C (4,010 °F; 2,480 K)

Solubility in water：insoluble

Crystal structure：Cubic

Application

The principal use of lanthanum hexaboride is in hot cathodes, either as a single crystal or as a coating deposited by physical vapor deposition. 

LaB6 is also used as a size/strain standard in X-ray powder diffraction to calibrate instrumental broadening of diffraction peaks.

LaB6 is a superconductor with a relatively low transition temperature of 0.45 K.