A RESONANT-PHOTOEMISSION STUDY OF YNI2B2C

Valence level photoemission measurements of the normal-state electroni c structure of the new boro-carbide intermetallic superconductor YNi2B 2C are presented. The behaviour of the Ni-dominated valence band peak at 1.4 eV binding energy and the states at E(F) across the Ni3p absorp tion threshold clearly indicate significant Ni3d contributions at thes e energies. In addition, the transfer of spectral weight from the main Ni3d valence band to a two-hole bound-state satellite at approximatel y 8 eV signals the role played by electron correlation in these materi als. The peak in the DOS predicted to lie at E(F) in band structure ca lculations is not observed in the experiment, possibly also due to the effects of electron correlation.