Density functional theory calculation of monolayer WTe2 transition metal dichalcogenides doped with H, Li and Be

Results based on density functional theory modelling of electronic and structural properties of single layer WTe₂ dichalcogenides doped with X (X=H, Li and Be) were presented. The generalized gradient approximation functional of Perdew, Burke, and Ernzerhof exchange correlation was used for all calculations. Formation energies of X dopant substituted for W ($X_W$) were obtained to be between 3.59 and 2.61 eV. The ${\mathrm{Li}}_W$ defect with energy of formation of 2.14 eV was energetically the most favourable. For all dopants considered, while the $H_W$ induced no magnetic moment, the ${\mathrm{Li}}_W$ and ${\mathrm{Be}}_W$ induced magnetic moments of 3.44 and 0.05 ${\mu }_B$, respectively. The band gap of the WTe₂ as a result of the dopants was populated with several orbital ground states, and thus reduced within a few eV. While all $X_W$ behave as $p-$ type dopant, the ${\mathrm{Li}}_W$ defect posses half metallic character.