IS THERE AN ELECTRONIC TOPOLOGICAL TRANSITION IN ZINC UNDER HIGH-PRESSURE

An electronic topological transition (ETT) in Zn was recently deduced from an anomaly in the Lamb-Mossbauer factor f at 6.6 GPa [Potzel et a l., Phys. Rev. Lett. 74, 1139 (1995)]. We show by inelastic neutron sc attering up to 9.3 GPa that the pressure dependence of the low energy acoustic phonon modes Sigma(4), Sigma(3), and T-4 is completely regula r without any singularity over the entire pressure range. No phonon so ftening was found beyond 6 GPa, in contrast to the Mossbauer studies. Lattice dynamical calculations demonstrate that, in general, the stron g decrease of f cannot be due to the q similar to 0 phonon modes sensi tive to the occurrence of an ETT. [S0031-9007(98)06729-5].