Effect of pressure on the structural, electronic and mechanical properties of ultraincompressible W2B

Abstract

The crystal structures of W₂B have been extensively investigated by the swarm structure searching method at ambient and high-pressure conditions. Our calculated thermodynamic enthalpy data suggests that the tetragonal phase with I4/m symmetry is the most stable at 0–50 GPa. The theoretical elastic properties and phonon spectroscopy confirmed that I4/m W₂B is both mechanically and dynamically stable. The calculated band structure and density of states show that I4/m W₂B is metallic and the electronic properties are sensitive to changes in external pressure with the occurrence of an electronic topological transition. The simulated high elastic modulus, hardness and strain–stress relationships reveal that W₂B exhibits excellent ultraincompressible properties and high strength. The combination of superior conductivity and mechanical properties reveals that W₂B can be used for hard coatings and electrical measurements.