On Apr 25, 2011, at 15:10 , Eduardo Ariel Menendez Proupin wrote: > > >The "two Fermi energies" of the constrained > >case need not to be exactly the same as the (single) > >Fermi energy of the unconstrained case, as long as the > >occupancies for spin-up and spin-down are the same in the > >two cases. > > Why not? Aren't the the energies and occupations related by > the Fermi-Dirac function?
they are (Fermi-Dirac or whatever function applies), but if you have a gap and a small broadening, the occupancies will do not (visibly) depend upon Ef for some interval of values > 2) tot_magnetization=1 > the spin up/dw Fermi energies are 6.3853 6.1614 ev > up: 4.8593 4.8594 5.2221 5.2221 5.2221 6.1335 6.1337 > 6.1338 > 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 > 1.0000 1.0000 Ef=6.3853eV is perfectly consistent with these occupations, as long as there are no states between 6.14eV and 6.40eV or so > > dw: 4.8796 4.8796 5.2528 5.2530 5.2531 6.1595 6.1596 > 6.1596 > 1.0000 1.0000 1.0000 1.0000 1.0000 0.6715 > 0.6660 0.6625 this is quite the same as case with spin magnetization not set P. --- Paolo Giannozzi, Dept of Chemistry&Physics&Environment, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
