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

摘要

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.