A Method of growing Anhydrous Single Crystals of Barium Azide

Abstract

THE salts of hydrazoic acid are of military interest owing to the fact that many of them are explosive. They range in sensitivity from sodium azide, which is stable, to the heavy metal azides, such as lead and gold azides, which are highly explosive. Intermediate in its explosive character is barium azide, which is sufficiently safe to be handled conveniently, yet can be made to explode. Solid state studies of this material have been hindered by the lack of suitable single crystal specimens. In particular, in order to study the photolysis of barium azide by electron spin resonance, crystals with a minimum size of about 5 × 2 × 1 mm are required. Although crystals of barium azide monohydrate are relatively easy to grow¹, it was felt that anhydrous crystals would offer a more simple system for study by electron spin resonance. This work was undertaken to develop a method of growing such crystals.