We have performed photoemission (PE) spectroscopy of β-ZrNCl and NaxZrNCl to study intercalation-induced change in the electronic structure. The valence band PE spectrum of β-ZrNCl shows a small intensity region within ∼2.5 eV of EF with a very small hump at E F that can be ascribed to hydrogen impurity states. These provide spectroscopic evidence that β-ZrNCl is an n-type semiconductor. Upon Na intercalation, new states possibly involving hybridized Zr4d and N2p systematically evolve at EF, with a negligible shift in the valence band structures. Similar results in β-HfNCl and NaxHfNCl indicate that these results represent common electronic features of the layered nitride chloride superconductors.
|Number of pages
|Physical Review B - Condensed Matter and Materials Physics
|Published - 2004 Nov