Structural, Elastic and Electronic Properties of ReO2

Structural, elastic and electronic properties of ReO2 are investigated by first-principles calculations based on density functional theory. The ground stateof ReO2 has an orthorhombic symmetry which belongs to space group Pbcn with a=4.7868 b=5.5736 , and c=4.5322 . The calculated bulk moduli are 322GPa, 353GPa, and 345GPa for orthorhombic, tetragonal, and monoclinic ReO2, respectively, indicating that ReO2 has a strong incompressibility. ReO2 is a metal ductile solid and presents large elastic anisotropy. The obtained Debye temperatures are 850K for orthorhombic, 785K for tetragonal, and 791K for monoclinic ReO2.