ON THE INTRINSIC CONDUCTIVITY OF POLYSULPHUR-NITRIDE

Polysulphur-nitride, (SN)(x), is an unusually interesting polymer. Its solid phase and that of the parent molecular crystal have the same sp ace group symmetry, with the same atoms and electrons per unit cell an d very slight differences in bond lengths. Yet, they have completely d ifferent electronic properties. Accurate electronic structure calculat ions have been carried out for the polymer and molecular crystal phase s at Hartree-Fock, Hartree and Local density Approximation levels. The results are qualitatively the same at these levels, and they are cons istent with experimental observations. This shows that correlation doe s not play a deciding role. The results also re-emphasize a way to syn thesize conducting polymers by polymerizing monomer molecules from the ir crystal phase. Simulations like in this work can be valuable to gui de synthesis.