It is a chemical compound named disulphur dinitride.
You can find more about it in this Wikipedia article:
http://en.wikipedia.org/wiki/Disulfur_dinitride
The chemical formula for disulphur dinitride is S2N2
The Lewis dot structure for the molecule containing the S2N2 keyword shows two sulfur atoms bonded to two nitrogen atoms with single bonds. Each atom has six valence electrons represented by dots around the symbol.
tetrasulfur tetranitrideS4N4 (w/ Ag2S catalyst) → 2 S2N2 (w/ 77K cold finger) → S2N2S2N2 (@ 0°C, sublimes to surface) → thermal polymerization → (SN)xelectrically conducting polymer
Tetrasulfur tetranitride is an inorganic compound with the formula S4N4. 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 S4N4 as their parent.Disulfur dinitride is the chemical compound S2N2 with a cyclic square planar structure It is not clear if S3N2 is Trisulfur dinitride or whether it really exists!