Angle-resolved photoemission study of the (100) surface of aZrN0.93single crystal

The (100) surface of a ${\mathrm{ZrN}}_{0.93}$ single crystal has been studied using angle-resolved photoemission and synchrotron radiation. A mapping of the bulk-band structure is presented and compared with an augmented-plane-wave band structure, calculated for stoichiometric composition. The experimentally determined bands are found to be located deeper below the Fermi energy than the calculated bands but the dispersions agree fairly well. A surface state is observed at 3.8 eV binding energy, for photon energies below 24 eV, and a structure interpreted as arising from vacancy induced states is observed at a binding energy of 2.1 eV for photon energies above 30 eV. The latter structure is found to exhibit a strong intensity modulation with photon energy. This intensity modulation is compared with the resonance enhancement observed in the emission from states just below the Fermi energy above the Zr 4p absorption threshold.