We present an atomistic model for predicting the distribution of doping electric charges in layered molybdenum disulfide (MoS$_{2}$). This model mimics the charge around each ion as a net Gaussian-spatially-distributed charge plus an induced dipole, and is able to predict the distribution of doping charges in layered MoS$_{2}$ in a self-consistent scheme. The profiles of doping charges in monolayer MoS$_{2}$ flakes computed by this charge-dipole model are in good agreement with those obtained by density-functional-theory calculations. Using this model, we quantitatively predict the charge enhancement effect in MoS$_{2}$ monolayer nanoribbons, with which strong ionic charge-localization effects are shown.
Comment: 18 pages, 7 figures