What is "tetrasulfur tetranitride"

n. (context inorganic compound English) a simple binary compound of sulfur and nitrogen, S₄N₄, having a ring structure; it is explosive

Tetrasulfur tetranitride is an inorganic compound with the formula SN. This gold-poppy coloured solid is the most important binary sulfur nitride, which are compounds that contain only the elements sulfur and nitrogen. It is a precursor to many S-N compounds and has attracted wide interest for its unusual structure and bonding.

Nitrogen and sulfur have similar electronegativities. When atoms are so evenly matched, they often form extensive families of covalently bonded structures. Indeed, a large number of S-N and S-NH compounds are known with SN as their parent.