Electronic interactions in metal-hydrogen solid solutions: ScHx, YHx, and V0.75Nb0.25Hx.

Abstract

The electronic interactions of hydrogen in a host metal lattice have been studied with synchrotron-radiation photoemission for low-x solid solution phases of ${\mathrm{ScH}}_{\mathrm{x}}$, ${\mathrm{YH}}_{\mathrm{x}}$, and ${\mathrm{V}}_{0.75}$${\mathrm{Nb}}_{0.25}$${\mathrm{H}}_{\mathrm{x}}$ for 0.15\ensuremath{\le}x\ensuremath{\le}0.25. For each system, a single well-defined hydrogen-induced feature is observed 5 eV below the Fermi level due to the local interaction of H with bonding metal-derived states, in agreement with linear combination of atomic orbitals save no evidence for hydride formation induced by cleaving the \ensuremath{\alpha}-phase hydride samples.