The unoccupied electronic structure of 1T-VSe₂

By use of angle-resolved inverse photoemission spectroscopy (ARIPES) in the isochromate mode using 9.88 eV photon energy the authors have studied the unoccupied electronic structure of 1T-VSe₂ along the principal symmetry directions Gamma M, Gamma M' and Gamma K. The data are found to be in good agreement with the recent ARIPES study of Law et al (1990) employing 20 eV photon energy. The experimental bands are reasonably well described by band-structure calculations but viewed together with the 20 eV data appear to be less dispersive perpendicular to the surface than theoretically predicted. A structure at 5 eV above E_F for normal incidence can be identified as an image potential state.