Hydrogen sulphide ions, decomposition

Metastable ion decomposition of hydrogen sulphide to give sulphur ions and molecular hydrogen has been investigated [247]. The metastable peak abundances were in the ratios 16 2 1 for H2S HDS D2S. 

For ions of initial structure (CH3CH2CH=SH)+ and (CH3CH=SCH3)+, average deuterium isotope effects, i, for metastable ion decompositions effecting loss of hydrogen sulphide of 2.3 and 1.8, respectively, were determined [136]. 

The formation of alkali-metal and alkaline-earth-metal sulphides and polysulphides from the elements in liquid ammonia has been extensively studied in the past, but the reactions between the metals and hydrogen sulphide in liquid ammonia have drawn detailed attention only recently. It has been suggested that the equilibrium of H2S in this solvent to give the solvated hydrosulphide ion accounts for the formation of KSH even with an excess of metal. With the alkaline-earth metals, effective preparative methods have been developed for the sulphides from H2S in liquid ammonia but anhydrous hydrosulphides have not been obtained. Now, hydrosulphides have been prepared of the form M(SH)2,xNH3 (M = Ca, Sr, or Ba x — 4, 6, or 0, respectively) from the metals with H2S in ammonia, but the compounds are stable only at low temperatures. Those of Ca and Sr are stable at —45 °C but decompose to the monosulphides at room temperature. Ba(HS)2 decomposes to BaS at 100 °C with evolution of a mole of H2S. For M (SH) (M = Rb or Cs), thermal decomposition gives polysulphides. The hydrosulphides of Rb, Cs, Sr, and Ba hydrolyse rapidly in moist air.74... 

---