The positive muon in the intermetallic hydride ZrV2Hx: A muon tracer study supplemented by differential thermoanalysis, neutron vibrational spectroscopy, and quasielastic neutron scattering

Abstract

ChemInform Abstract (phase diagram, structural and dynamical properties of the ZrV2/H system).

Arrhenius Jump Rate of Muons in Metals and Metallic Compounds

“…In this alloy muon is found [13] static up to 50 K. For T > 50 K, the muon diffuses in a tunnelling process and over 50-250 K the under-barrier jump rate for muon diffusion is described by the formula This result can be explained by the present theory which assumes the tunnelling of muon under a potential barrier (H). Using the potential barrier for hydrogen diffusion (Hp ) = 1000 K [14] and considering the isotopic reason, H is set equal to 1000 K. Then for b = 3 Å, β becomes 2.3 x 10-6 .…”

Inelastic neutron scattering evidence for anomalous H–H distances in metal hydrides

“…measurements at high energies (24). The situation is different for acoustic phonons, which occur at low energies with the effective mass dominated by the metal atoms (25).…”

“…Finally, we considered whether the peak is associated to hydrogen vibrations in pure vanadium. Under certain conditions (24), ZrV2Hx can segregate into a Zr-rich alloy and VHx phases. The dominant feature of INS of VHx is around 55 meV (26) (SI Appendix, Figs.…”

Arrhenius Jump Rate of Muons in Some Non-Stoichiometric Metallic and Intermetallic Hydrides

“…Then for the barrier width b=0.5 Å , the barrier transparency coefficient β becomes 10 -2 . Therefore the jump rate formula becomes This formula finds a good comparison to the experimental values at temperatures above 300 K. Muon diffusion in ZrV2Hx has been studied over the temperature range 2-250 K [18]. In this study muon in found to remain immobile for T < 50 K above which the muons start to diffuse.…”