pristine semiconductor surfaces may show dangling bonds which correspond to partially filled electronic surface states in the gap. Nature dislikes this situation and semiconductor surfaces reconstruct , even in rather complicated ways, in order to eliminate these partially filled surface states. Passivating with hydrogen is a computationally easy way to saturate these dangling bonds without inducing large reconstructions/relaxations. If your surface does not show dangling bonds you do not need to passivate them. best, stefano
peyman amiri wrote: > I am working on a (100) free surfaces of NaCl type MnSe structures with (1 1 > 1) AF order, after passivation of Mn & Se surface atroms by Hydrogen atoms > the band gap reduces a little (in compare of free surface without > passivation) and from the results of cohesive energy we saw that the free > surface MnSe is more stable than the free surface after passivation. Now i am > sure that passivation is not needed in my work. > > How can i show and prove this matter? > > May these results be due to a computational errors? > > In principle when does we need to passive the semiconductor surfaces? > > Any suggestions will be appreciated. > Thanks > Peiman > ====================================== > Peiman Amiri > Computational Condensed Matter Research Lab > Physics Department, Isfahan University of Technology, Iran > > Tel lab: +98 311 391 3733 Fax Office: +98311 391 3746 > ------------------------------ > > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum >
