No abstract

No abstract

We report investigations of Zn metal under quasi-hydrostatic pressures up to 16 GPa by 67 Zn Mössbauer spectroscopy and scalar-relativistic linearized augmented plane wave (LAPW) calculations. Our studies show that at 4.2 K an electronic topological transition (ETT) occurs at about 6.6 GPa, corresponding to a volume change of (1−V /V • ) ≈ 0.085. At the ETT conduction electron states in the third Brillouin zone at the symmetry point L ('butterflies') move below the Fermi surface and start being occupied. At the ETT the electric field gradient tensor and the s electron density ρ(0) at the 67 Zn nucleus remain virtually unchanged, but the lattice dynamics is drastically affected. The Lamb-Mössbauer factor (LMF) abruptly drops by a factor of two between 6.5 and 6.7 GPa and the curvature of the pressure dependence of the second-order Doppler shift (S SOD ) changes markedly. The results on LMF and S SOD are described by a sudden destruction of a giant Kohn anomaly which accompanies the ETT.