Beryllium nitride, , is a nitride of beryllium. It can be prepared from the elements at high temperature (); unlike beryllium azide or , it decomposes in vacuum into beryllium and nitrogen. It is readily hydrolysed forming beryllium hydroxide and ammonia. It has two polymorphic forms: cubic with a defect anti-fluorite structure, and hexagonal . It reacts with silicon nitride, in a stream of ammonia at to form .
Preparation Beryllium nitride is prepared by heating beryllium metal powder with dry nitrogen in an oxygen-free atmosphere at temperatures between :
Uses It is used in refractory ceramics as well as in nuclear reactors.
It is used to produce radioactive carbon-14 for tracer applications by the + + reaction. It is favored due to its stability, high nitrogen content (50%), and the very low capture cross section of beryllium for neutrons.
Reactions Beryllium nitride reacts with mineral acids producing ammonia and the corresponding salts of the acids:
In strong alkali solutions, a beryllate forms, with evolution of ammonia:
Both the acid and alkali reactions are brisk and vigorous. Reaction with water, however, is very slow:
Reactions with oxidizing agents are likely to be violent. It is oxidized when heated at in air.
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