Phosphorus Monoselenide, P₂Se

Phosphorus Monoselenide, P₂Se, may be obtained by heating one atomic proportion of selenium with two atomic proportions of phosphorus in a current of hydrogen. It is formed with incandescence as a clear red solid, which is combustible and slightly soluble in carbon disulphide. It is decomposed by boiling alkalis with liberation of phosphine. With metal selenides it forms double selenides.