Molybdenum sesquisulphide

A French paper described direct electrolytic deposition of molybdenum disulphide and molybdenum sesquisulphide from a mixed aqueous bath of ammonium molybdate and ammonium sulphide. G W Rowe and his co-workers produced a molybdenum disulphide coating on molybdenum wire by electrochemical deposition from a... 

Molybdenum Sesquisulphide, MO2S3.—When the disulphide, compressed into small bars, is heated in an electric ftirnace, a metallic mass is produced which consists of the sesquisulphide, M02S3, contaminated with metallic molybdenum. On removal of the latter vith aqua regia, there are obtained steel-grey needles, of density 5-9, which are readily reduced to the metal by heating in hydrogen, or converted to the disulphide by heating in sulphur-vapour. ... 

The sesquisulphide Mo Sj is said to have been prepared by rapid heating of the disulphide in the absence of air, and extraction with cold dilute aqua regia, or by combination of molybdenum and sulphur at 1300°C °. 

Molybdenum disulphide is decomposed— yielding the sesquisulphide and molybdenum—only at the temperature of the electric furnace. It is attacked by chlorine, bromine, nitric acid, sulphuric acid, and, when strongly heated, by hydrogen or water-vapour, but not by alkalies. The specific heat of the naturally occurring molybdenite is 0T067 (Neumann), and of the artificial, 0T233 (Regnault). 

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