Silicon monosulphide

Lagerquist, A., G. Nilheden, and R. F. Barrow The Near Ultra-Violet Band-System (D—X) of Silicon Monosulphide. Proc. physic. Soc. A 65, 419-433 (1952). 

Solid silicon monosulphide in an amorphous form has been prepared by the condensation of gaseous SiS at high temperatures. Vaporization and vapour pressure data suggest that SiS is metastable, disproportionating into SiS2 and silicon at an appreciable rate above 950 K. SiS appears to be thermodynamically unstable below 1452 K. Vaporization of solid SiS2 yields predominantly SiS and S2 species according to the dissociation process ... 

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