Effects of the Hubbard U correction on the electronic and magnetic properties of the tetragonal V 2 P 2 sheet.

A recent theoretical work predicted the orthorhombic phase of the V 2 P 2 sheet with the half-metallic electronic property using a linear combination of atomic orbitals (LCAO) basis set based on density functional theory (DFT). However, in the plane-wave DFT method, the tetragonal (t) V 2 P 2 phase is the ground state structure. The total energy of the optimized tetragonal V 2 P 2 is 0.91 eV per cell lower than that of the orthorhombic phase. Herein, we investigated the effects of Hubbard U correction onthe electronic, magnetic, and adsorption properties of the t-V 2 P 2 sheet. The t-V 2 P 2 sheet is found to be dynamically and mechanically stable. The t-V 2 P 2 sheet prefers an antiferromagnetic ground state with an indirect narrowed bandgap of 0.23 eV. The estimated electron mobility in the t-V 2 P 2 sheet at room temperature is approximately 24 times that of a hole. The t-V 2 P 2 sheet exhibits a sizable magnetic anisotropy (MAE) of 69.63 μeV per V atom with in-plane magnetization. Mean-field approximation based on the 2D classical Heisenberg model predicts a high Néel temperature ( T N ) of the t-V 2 P 2 sheet up to 1263 K. The Li atom adsorption on the t-V 2 P 2 sheet shows a transition from semiconductor to metal. Also the Li-V 2 P 2 system has a residual integer magnetic moment of 1 μ B . Due to strong steric coulomb repulsion, the minimum diffusion energy barrier ( E a ) for the Li-ion on the t-V 2 P 2 surface is high enough to make the Li atom immobile. Our findings demonstrate the potential of the t-V 2 P 2 sheet for antiferromagnetic spintronics and sensing applications.