Noun
polysulfide (plural polysulfides)
(chemistry) Any compound of general formula RSnR having a chain of more than two sulfur atoms; any derivative of a polysulfane.
Blue, violet, and pink The nature of the polysulfide dictates the color of the solid. Source: Internet
It is not an iron(IV) compound, but is actually an iron(II) polysulfide containing Fe 2+ and Smain ions in a distorted sodium chloride structure. Source: Internet
Some of these cages contain polysulfide ( Smain ) groups that are the chromophore (color centre). Source: Internet