Polymeric Sulphur Nitride

The —CF3 derivative is also a product in the reaction of S4N4 with CF3SO2OSO2CF3, but of more importance is the S3N2 radical cation (20), which is also produced in the reaction as the CF3SOJ salt. ° An independent study has 

The direct synthesis of the S4NJ ion from S4N4 has been described when sodium azide and S4N4 are stirred together in ethanol, Nj gas is evolved, elemental sulphur is precipitated, and a deep orange solution containing Na S4N7 is formed [equation (20)]. This synthetic route provided some support for the 

Niinisto and R. Laitinen, Inorg. Nuclear Chem. Letters, 1976, 12, 191. 

The solubilities of heptasulphur imide in eleven organic solvents have been measured. S7NH has been found to react with SOCI2 to give colourless crystals of (S7N)2S0, for which i.r., Raman, and mass spectral data have been reported. The data indicate that the geometry at the nitrogen atom is planar.  

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Possibly the most important single advance in the field of synthetic inorganic polymers in recent years has been the discovery, in 1973, that polymeric sulphur nitride (SN)n (Polythiazyl) is a metallic-type conductor, which at low temperatures becomes superconducting. Polythiazyl is the first known example of such a polymeric superconductor, which does not contain metal atoms. A history of (SN)r research to 1973, and a review of the chemical properties and preparative... 

Alternate manbers of series (c) may be regarded as ionised dimers of series (a), but they are different compounds and can be distinguished from the latter by their melting points and other characteristics. The simplest member of series (b) with n = 1, is formed together with more highly polymeric material, in a reaction between phosphorus trichloride and sulphur nitride. 

Poly(sulphur nitride) is obtained as gold-coloured fibrous crystals from the solid-state polymerization of SN crystals. At room temperature its conductivity is in the region of 10 S m and this can be increased an order of magnitude by chemical modification with bromine. 

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