Electronic structure and elastic properties of TiB2 and ZrB2

We investigate the electronic structure and elastic properties of TiB2 and ZrB2. The electronic properties are computed within the framework of density functional theory (DFT) based on linear combination of atomic orbitals (LCAO), full potential linearized augmented plane wave (FP-LAPW) and projector augmented wave (PAW) methods while the elastic properties are calculated using the PAW method. The calculated electronic and elastic properties of TiB2 and ZrB2 are found to be in good agreement with earlier data. In addition, the theoretical directional and spherically averaged Compton profiles of TiB2 and ZrB2 are also computed using the LCAO method. The spherically averaged theoretical values are compared with the first-ever measurement on polycrystalline ZrB2. To estimate the charge transfer in ZrB2, ionic model based calculations have also been performed which suggest transfer of electron from Zr to B atoms.