Ab initio calculations of structural, elastic and electronic properties of Li2O2

The equilibrium structure of the compound Li2O2 has been obtained via minimization of the total energy within the local density approximation (LDA) based on density functional theory (DFT). The calculated lattice parameters are in excellent agreement with available values. The elastic properties of Li2O2 are investigated. Values of all independent elastic constants (C-11, C-12, C-13, C-33 and C-44) as well as bulk moduli in the a and c directions are predicted. Our calculated elastic properties suggest that the compound Li2O2 is slightly anisotropic but can be considered as an isotropic material compared with other highly anisotropic materials. The electronic properties, including the density of states and energy band structure, are obtained and we find that this compound behaves as a semiconductor.