The pseudo potentials you use correspond to the following atomic valences: Zn.pbe-van.UPF : 12 Al.pbe-sp-van.UPF : 11 O.pbe-van_ak.UPF : 6
Therefore, the total amount of electrons per unit cell, as printed in the output (that you should carefully read!) is: 12 * N_Zn + 11 * N_Al + 6 * N_O = 12 * 8 + 11 * 16 + 6 * 32 = 464 This corresponds, if my calculation is not wrong, to 464 / 2 = 232 occupied bands. If you specify, as you do, nbnd= 200 in the input file for the non self-consistent calculation, the gap you calculate is not between the highest occupied and the lowest unoccupied bands, but between low energy occupied bands. Giovanni > On 15 May 2015, at 16:02, Winfred Mulwa <[email protected]> wrote: > > Dear all, > I am calculating the band gap of ZnAlO4 using the attached inputfile. > My results show a band gap of 10eV compared to experimental value of 3.8eV. > Please somebody tell me where i went wrong. > Regards > Mulwa Winfred. > D Phil Student, Computational Material Science Group, > University of the Free State - QwaQwa, > South Africa. > <sv.bands.in>_______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum -- Giovanni Cantele, PhD CNR-SPIN c/o Dipartimento di Fisica Universita' di Napoli "Federico II" Complesso Universitario M. S. Angelo - Ed. 6 Via Cintia, I-80126, Napoli, Italy e-mail: [email protected] Phone: +39 081 676910 Skype contact: giocan74 ResearcherID: http://www.researcherid.com/rid/A-1951-2009 Web page: http://people.na.infn.it/~cantele _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
