Lithium monosulphide

Lithium monosulphide, Li2S.—The monosulphide can be prepared by direct synthesis or by reduction of the sulphate with charcoal. The yellow, product is amorphous, but heating in the electric furnace transforms it into transparent cubes 8 of specific gravity 1 63 to 1 7. Evaporation of its aqueous solution yields hygroscopic crystals of the hydrosulphide, LiSH ... 

The preparation of the alkali monosulphides.—Products usually called sulphides have been obtained by the direct union of the elements. Thus, L. Troost 2 prepared what he regarded as amorphous lithium sulphide, Li2S, by the action of sulphur vapour on heated lithium. H. Davy, and J. L. Gay Lussac and L. J. Thenard, prepared sodium sulphide, Na2S, by warming sulphur with sodium ... 

Lithium polysulphides-—Fusion of lithium hydroxide with sulphur yields a yellow mass like liver of sulphur, probably consisting of polysulphides of lithium. Berzelius isolated a hydrated disulphide, Li2S2, iH20, by concentrating an aqueous solution of the monosulphide. 

The monosulphide and polysulphides are formed by burning the metals in sulphur vapour, by the action of sulphur on the metals dissolved in liquid ammonia, and by the action of the molten metals on sulphur dissolved in toluene. Hydrates or alcoholates and, in some cases, the anhydrous compounds may be prepared by dissolving sulphur in hot solutions of the hydrosulphides or monosulphides. Potassium, rubidium and caesium give all the sulphides where = 1, 2, 3, 4, 5, or 6 sodium only up to the pentasulphide, and lithium only those for which x = 1, 2 and 4 (Pearson and Robinson, 1931). All the metals form two polysulphides of relatively outstanding stability one is invariably the disulphide, and the other tetrasulphide in the case of lithium or sodium, and pentasulphide in the case of potassium, rubidium or caesium. The amount of water of crystallisation and the solubility decrease with increase in atomic number of the metal, the gradation being most marked between sodium and potassium. 

Lithium (aluminium) iron monosulphide secondary batteries 9/18... 

Table 9.17 Charecteristics of lithium (aluminium)ron monosulphide batteries...

This battery is seen as a possible contender in the electric vehicle market. Eagle Richer, Gould and Argonne National Laboratory are involved in these developments. Of various samples studies the lithium (alu-minium)-iron monosulphide (LiAL-FeS) secondary system is the closest to commercial realization. 

Barton and his group have prepared the interesting new di-t-butyl thio-ketone (7) in high yield by reaction of carbon disulphide with the lithium salt of the corresponding ketone imine. Independently, Ohno and his co-workers have published an analogous synthesis of this non-enethiolizable thioketone (7). Aliphatic thiones and, possibly, enethiols have been obtained by reaction of arylimines with benzoic anhydride and a stream of hydrogen sulphide. Treatment of a vinyl chloride with sodium monosulphide led to the isolation of thio-dimedone (8 R = H), which has an enethiol ketone structure. Basic hydrolysis... 

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