Beryllium telluride (BeTe) is a chemical compound
whose molecular weight is 136.6122 g/mol. Its CAS
number is 12232-27-8 and it has a density of 5.12 g/
cm3. Its structure is one of the sphalerite cF8 group
with a space group of F43m (#216). It is a crystalline solid
with face-centered symmetry, a = 5.615 ? at 300 K.
It can be prepared by heating the elements together in
an inert atmosphere:
Be+ Te+ heat ? BeTe
Te melts at 450°C and Be melts at 1287°C. A heating
temperature of 750°C is sufficient to cause complete
reaction. BeTe is a crystalline solid with the lattice
constant of 0.5615 nm. It is a semiconductor with a large
energy gap of around 3 eV. Toxicity is unknown, but
both beryllium and tellurium are toxic. Toxic H2Te gas
is evolved on exposure to water.
Gray powders, decomposing relatively rapidly in air. Crystallize
in structure type B3 (ZnS type), d (BeSe) 4.32, d (BeTe) 5.09.
