Results of total energy local density calculations for the effect of pressure on the lattice parameters, bond lengths, electronic structure and A1g phonon frequency in HgBa2CuO4 have been carried out. The effects of pressure on the frequency of the apical-oxygen (OA) A1g phonon in the Hg-OA-Cu bonds are studied in order to understand the role of pressure in increasing Tc of mercury-based superconductors. Theoretically determined zero pressure lattice parameters and phonon frequencies are in good agreement with experiments. An electronic topological transition that occurs when the van Hove singularity is shifted close to the vicinity of EF by pressure causes considerable phonon softening and anomalous behavior of c-axis length, the Hg-OA bond and Ba z-coordinate.
|Journal||Journal of the Korean Physical Society|
|Issue number||SUPPL. Part 1|
|Publication status||Published - 1996|
ASJC Scopus subject areas
- Physics and Astronomy(all)