CORE ELECTRON SPECTROSCOPIC STUDIES OF YNI2B2C

High-energy electron energy-loss spectroscopy in transmission has been applied to obtain the absorption spectra at the B 1s, C 1s and Ni 2p( 3/2) excitation edges of bulk polycrystalline YNi2B2C. We find a close similarity in the near-edge structures and confirm the strongly coval ent character of the bonding between Ni, B and C. We compare our resul ts to band structure calculations of the local unoccupied density of s tates generated within the local density approximation. From x-ray pho toemission spectroscopy measurements we determine the core level bindi ng energies and from a comparison of photoemission and Auger spectrosc opic measurements we derive a value of the Ni d-d Coulomb energy U-A o f about 4 eV. Copyright (C) 1996 Elsevier Science Ltd.