Ab-initio computations of electronic, transport, and structural properties of zinc-blende beryllium sulfide (zb-BeS)

We have studied the electronic, structural, and transport properties of the zinc-blende beryllium sulfide (zb-BeS), using density functional theory (DFT). We employed a Local Density Approximation (LDA) potential and the Linear Combination of Atomic Orbitals (LCAO). Our computational method leads to the ground state of the materials without utilizing over-complete basis sets. Our calculated, indirect band gap is 5.44 eV, from Г to a conduction band minimum between Г and X, for a room temperature lattice constant of 4.863 Å, is in excellent agreement with experiment which indicates the lower limit of 5.5 eV for the indirect band gap. We also report the total (DOS) and partial densities of states (pDOS), electron and holes effective masses, the equilibrium lattice constant, and the bulk modulus. Our calculated bulk modulus of 107.7 GPa is in excellent agreement with experiment (105 GPa). Our predicted equilibrium lattice constant at zero temperature is 4.814 Å.