Unoccupied surface-state band on Si(111) 2×1

Employing k-resolved inverse-photoemission spectroscopy, we have measured the dispersion of the unoccupied electronic surface-state band of cleaved single-domain Si(111) 2×1 along the J and J symmetry directions. The energy dispersion and general shape of the measured surface-state band agree well with the calculated band of the -bonded chain model. © 1987 The American Physical Society.