Hh. Weitering et al., BAND DISPERSIONS OF THE PI-BONDED-CHAIN RECONSTRUCTION OF SI(111)3X1-LI - A CRITICAL-EVALUATION OF THEORY AND EXPERIMENT, Physical review. B, Condensed matter, 54(15), 1996, pp. 10585-10592
The surface-state band-structure of the three-domain Si(111) 3 x 1-Li
reconstruction has been determined using angle-resolved photoemission.
Experimental band dispersions are compared to theoretical calculation
s for the extended Pandey model and the Seiwatz model. Even though the
extended Pandey model is favored on the basis of scanning tunneling m
icroscopy and total-energy considerations, the calculated surface stat
es are inconsistent with experiment. The calculated states for the Sei
watz model are consistent with the experimental dispersion along the m
ain symmetry direction (<(Gamma)over bar> (A) over bar) but serious di
screpancies exist in other parts of the Brillouin zone. The disparity
between the density-functional-theory calculations and experiment indi
cate that exchange and correlation in pi-bonded Si chains may need to
be analyzed beyond the mean-field band-structure approach.