Quantum-chemical study of structural and electronic properties of a new tin monosulfide polymorph π-SnS

By means of the density functional theory (DFT) method, the electronic structure of the new tin monosulfide polymorph π-SnS has been calculated, its unit cell parameters have been optimized, and the relative enthalpy of formation and bulk modulus have been evaluated and compared with known and well-characterized crystalline and two-dimensional SnS modifications. It has been demonstrated that the π-SnS polymorph ranks next in stability to thermodynamically stable α-SnS. The new modification is predicted to be a semiconductor with a wider band gap than for α-SnS. It has been shown that identification of π-SnS in nanocrystalline SnS samples by X-ray crystallography could be considerably complicated by overlapping with broadened reflections of α-SnS.