LIFETIME BROADENING IN ANGLE-RESOLVED PHOTOEMISSION

In a recent letter [A.B. McLean, C.E.J. Mitchell and I.G. Hill, Surf. Sci. 314 (1994) L925] it was suggested that life-time broadening alone could explain why surface state photoemission line-widths have been o bserved to increase as the initial states approach the Fermi level. I wish to point out that the used model is unphysical, that the agreemen t with experimental data is quite fortuitous, and that the experimenta l observations are satisfactorily understood in terms of established m odels.