Electronic band structure and magnetic properties of I vacancy and nonmetallic atoms doped single layer PbI 2

Abstract We systematically explore the influence of I vacancy and a series of substitutional nonmetallic atoms, including F, Cl, Br, Si, P and S, on the stability, geometric structure, electronic structure and magnetic properties of single layer PbI 2 using first-principles calculations. The results show that I vacancy and nonmetallic atoms X doped single layer PbI 2 are stable at room temperature, although substitutional atom X and I vacancy lead to the local structure deformation. Moreover, substitutional F, Cl and Br dopants do not induce the magnetism in doped single layer PbI 2 due to same number of valence electron of F, Cl, Br and I, while ground states of I vacancy, S, P and Si doped system are magnetic and the magnetic moments induced by one I vacancy, S, P and Si atom are 1.0, 1.0, 2.0 and 3.0 μ B , respectively. It is found that the distribution of the magnetic moment induced by I vacancy and doping atom relate to the hybridization between doping atom and its neighboring Pb and I atoms or the hybridization between Pb and I atoms around vacancy. Remarkably, although the spin–orbit coupling (SOC) induce spin splitting of the electronic bands due to the absence of inversion symmetry in I vacancy and nonmetallic atoms X doped single layer PbI 2 , the SOC does not alter the electron occupation of the bands near the Fermi level. As a result, the magnetic moment induced by I vacancy, S, P and Si atoms are not changed and the magnetic moment of F, Cl and Br doped single layer PbI 2 are still zero after the inclusion of SOC.