First-principles calculations of structural, electronic and elastic properties of Ca2MgSi2O7

We studied the structural, electronic and elastic properties of åkermanite, Ca2MgSi2O7, by using the first-principles method. The structure of åkermanite is constructed by interleaved tetrahedral and Ca cation layers, and this characteristic is perfectly presented by three-dimensional (3D) crystal lattice, as well as two-dimensional (2D) contour plots of total electron densities in this paper. The chemical bonding and interaction are investigated by analyzing the bond population and density of states (DOS) of the crystal. Theoretical elastic constants of åkermanite are consistent with the experimental values. Moreover, significant anisotropy for Young's modulus can be observed.