It has a layer structure with Mo atoms in trigonal prismatic coordination sandwiched between sheets of S atoms. It is unreactive towards water and acids and alkalis. However, molybdenum disulfide and other Mo-S compounds oxidise when heated in air to molybdenum trioxide. Because of the unreactivity of molybdenum disulfide Mo-S compounds are made via reaction with molybdates as in the preparation of hydrodesulfurisation catalysts. Molybdenum disulfide is used, per se, as a dry lubricant.
Molybdenum forms complexes with sulfide ([MoS4] 2-) and many organosulfur ligands. These compounds unlike their oxygen counterparts are often brightly coloured, e.g. [MoS4] 2- is deep orange-red. The dithiocarbamates and dithiophosphates are applied as oil soluble lubricant additives.