In my test calculation the Fermi enrgy was -7.33 eV.
Sent from Samsung Mobile -------- Original message -------- From: 毛飞 <[email protected]> Date:2015/08/07 2:59 PM (GMT+05:00) To: [email protected] Cc: [email protected],[email protected] Subject: Re:[SIESTA-L] The energy band gap of LiF Dear Zhen and Rahman It can be seen from the E(k), the bangap at the Gamma point is 19.5 eV, it is a little larger than anywhere else (see attachment). Does it strange? The Fermi energy is at -7.44 eV, which is read from the *.bands file. Rahman, do you test the LiF calculation with the same input file with me, if not, can you show me the input file? I want to know what is the difference between them, and obtain the correct band structure of LiF. Thank you in advance. Regards, Fei 在2015-08-07，Zhen Zhu <[email protected]> 写道: -----原始邮件----- 发件人: Zhen Zhu <[email protected]> 发送时间: 2015年8月7日 星期五 收件人: Gul Rahman <[email protected]> 抄送: "[email protected]" <[email protected]> 主题: Re: [SIESTA-L] The energy band gap of LiF Hi Fei, are you sure your Fermi level is correct? --Zhen On Thu, Aug 6, 2015 at 11:43 PM, Gul Rahman <[email protected]> wrote: Are you calculating the bandgap at the Gamma Point? It is around 8.40 eV at Gamma point (my test calculation). Sure, this will be different at the other symmetry points in the BZ. Gul Dr. Gul Rahman Assistant Professor, Department of Physics, Quaid-i-Azam University, Islamabad, Pakistan http://www.qau.edu.pk/profile.php?id=818020 On Thursday, 6 August 2015, 16:36, 毛飞 <[email protected]> wrote: Dear Zhen and Rahman Thank you for your useful suggestions. Please excuse me to bother you again. I calculate the band structure of LiF again, and I think I have already corrected the errors in the new input file, but the result is still unreasonable, the band gap of LiF is 15.8 eV (it is too large). You are right, the structure of LiF is the same with NaCl. I define the primitive cell as the simulation cell (see block LatticeVectors) in the input file. Regards, Fei #################### Input file ####################### SystemName bulk.LiF SystemLabel bulk_LiF NumberOfAtoms 2 NumberOfSpecies 2 %block ChemicalSpeciesLabel 1 3 Li 2 9 F %endblock ChemicalSpeciesLabel # basis PAO.BasisSize DZP PAO.EnergyShift 200 meV LatticeConstant 4.08 Ang # Lattice constant alat %block LatticeVectors # primitive cell 0.000 0.500 0.500 0.500 0.000 0.500 0.500 0.500 0.000 %endblock LatticeVectors %block kgrid_Monkhorst_Pack 10 0 0 0.0 0 10 0 0.0 0 0 10 0.0 %endblock kgrid_Monkhorst_Pack BandLinesScale ReciprocalLatticeVectors %block BandLines 1 0.0 0.0 0.0 # Gamma-point 20 0.5 0.0 0.5 # X-point 30 0.5 0.25 0.75 # W-point 30 0.375 0.375 0.75 # K-point 30 0.0 0.0 0.0 # Gamma-point %endblock BandLines %block ProjectedDensityOfStates -20 10 0.1 300 eV %endblock ProjectedDensityOfStates MeshCutoff 300.0 Ry # SCF options MaxSCFIterations 100 # Maximum number of SCF iter DM.NumberPulay 3 # One Pulay every 3 iter DM.MixingWeight 0.35 # New DM amount for next SCF cycle DM.Tolerance 5.d-4 # Tolerance in maximum difference SolutionMethod diagon # OrderN or Diagon OccupationFunction FD ElectronicTemperature 25 meV # Temp. for Fermi smearing # exchange-correlation functional
