Polysulfur-nitride

The discovery in 1973 that polysulfur nitride (SN)X, a polymer comprised only of non-metallic elements, behaves as a superconductor at 0.26 K sparked widespread interest in sulfur-nitrogen (S-N) chemistry. In the past 30 years, the field of inorganic S-N chemistry has reached maturity and interfaces with other areas of chemistry, e.g., theoretical chemistry, materials chemistry, organic synthesis, polymer chemistry and biochemistry, have been established and are under active development. This interest has been extended to Se-N and, to a lesser extent, Te-N systems. 

Greene RL, Street GB, Suter LJ (1975) Superconductivity in polysulfur nitride (SN)x. Phys Rev Lett 34 577-579... 

Labes MM, Love P, Nichols LF (1979) Polysulfur nitride - a metallic, superconducting polymer. Chem Rev 79 1-15... 

In contrast to the nonconducting polymers, such as hdpe, polysulfur nitride (SN) is a conductor of electricity at ordinary temperatures, and this property is enhanced as the temperature is lowered. The polymer (SN) is an anisotropic superconductor at 0.3 K. This conductivity is related to a trans planar conformation of chains with delocalized it orbitals. 

Electronic Structure and Optical Properties of Polysulfur Nitride, (SN)x 575... 

The self-consistent-field (SCF) ab initio Hartree-Fock crystal orbital method is applied with success to polysulfur nitride (SN)X, chains using non-local exchange and evaluating all integrals over atomic orbitals within 5 atomic neighbours accurately. 

Polysulfur nitride and tranj-acetylene as molecular wires, switches, and valves [18]... 

V. V. Walatka, M. M. Labes, and J. H. Perlstein, Polysulfur Nitride—chai22a One-Dimensional Chain with a Metallic Ground State, Phys. Rev. Lett., 31, 1139-1142 (1973). 

L. Pintschovius, Polysulfur nitride, (SN) c, the first example of a polymeric metal. Colloid Polym. Sci. 256,883 (1978). 

P. Love, Some properties and applications of polysulfur nitride. Polymer News 7,200 (1981). 

Thiazanes are inorganic polymers like polyphosphazenes but with phosphorus atoms in the chain replaced by sulfur. They are electron-conducting covalent polymers that are analogous to solid polysulfur nitride. Electron-conducting polymers such as polythiazanes are too reactive for use in air because they are radicals a free unpaired valence electron or an electron hole is in chemical language a radical, and radicals happen to be very reactive. 

Sulfur nitride polymer (polysulfur nitride, polythiazyl) [-(SN)-]n. First synthesized in 1910 but ignored for six decades, this covalent polymer has been restudied and found to have the physical and electrical properties of a metal. It is formed by passing the vapor of (SN)4 over a catalyst that cracks it to (SN)2, which is condensed on a cold surface where it spontaneously polymerizes into crystalline form. The crystals are malleable and can be cold-worked into thin sheets or fibers under pressure, having an electrical conductivity similar to that of mercury, and superconducting near 0 K. 

A key discovery was made in 1973, when the inorganic polymer polysulfur-nitride (SN) was found to be a metal [1]. The conductivity of (SN) at room temperature is about 10 S cm" below a critical temperature of about 0.3 K, (SN) becomes a superconductor [2]. Unfortunately (SN), is explosive and no commercial application was possible. 

The study of binary compounds of sulfur and nitrogen has been spurred both by the problems they pose to simple bonding theory and by the observation that polysulfur nitride is metallic in its properties. 

H. Kahlert and K. Seeger, "Electrical Properties of Polysulfur Nitride, (SN) ", Proc. 13th Int. Conf. Phys. Semicond., Rome, Aug. 19 6. 

The interesting physical properties of the inorganic polymer (SN) (polysulfur nitride) as a highly anisotropic metal at higher temperatures... 

Sulfur Nitride Polymer n (polysulfur nitride, polythiazyl) [-(SN)-]n. First synthesized in 1910 but ignored for 6 decades, this covalent polymer has been restudied and found to have the physical and electrical... 

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