On Mon, 24 Mar 2008, Chao Cao wrote: CC> So, no one has any idea?
i'd expect that most people, who would feel qualified to answer, are currently in easter holidays. there are countries where those are taken much more seriously than the US (and include easter monday)... axel. CC> CC> CC> Chao Cao wrote: CC> > Dear PWSCF users and developers: CC> > CC> > I have been trying to use PWSCF's implementation of LDA+U to calculate CC> > the electronic structure of CaCuO2 lately. In VASP, once I turn on U, it CC> > gives AFM ground state and reasonable gap separation at E_F. However, CC> > the procedure seems to be much harder for PWSCF. While it gets AFM gs CC> > correctly, I can never get a band gap. I searched the forum, and I CC> > realized that the initial occupation number might be important, but the CC> > several combinations I tried seem to give me the same result. So, is CC> > there any hint or suggestions, especially how to choose initial CC> > occupation numbers? Thanks in advance. CC> > CC> > CC> > Best, CC> > CC> > Chao Cao CC> > CC> > CC> > And, here's my input file: CC> > CC> > &control CC> > calculation = 'scf' CC> > restart_mode = 'from_scratch' CC> > prefix = 'CaCuO2' CC> > disk_io = 'low' CC> > outdir = './' CC> > / CC> > &system CC> > ibrav = 0, celldm(1) = 1.88972688, ntyp = 4, nat = 16 CC> > nbnd=80, ecutwfc = 32, ecutrho = 400 CC> > nspin = 2, starting_magnetization(2)=0.5, starting_magnetization(3)=-0.5 CC> > lda_plus_u = .true., Hubbard_U(2) = 6.5, Hubbard_U(3) = 6.5 CC> > occupations = 'smearing', smearing = 'mp', degauss = 0.007 CC> > / CC> > &electrons CC> > mixing_beta = 0.2 CC> > conv_thr = 1.0d-9 CC> > / CC> > ATOMIC_SPECIES CC> > Ca 1.0 Ca.pbe-nsp-van.UPF CC> > Cuu 1.0 Cu.pbe-n-van.UPF CC> > Cud 1.0 Cu.pbe-n-van.UPF CC> > O 1.0 O.pbe-van.UPF CC> > ATOMIC_POSITIONS crystal CC> > Ca 0.25 0.75 0.25 CC> > Ca 0.75 0.25 0.25 CC> > Ca 0.25 0.75 0.75 CC> > Ca 0.75 0.25 0.75 CC> > Cuu 0.25 0.25 0.00 CC> > Cuu 0.75 0.75 0.50 CC> > Cud 0.75 0.75 0.00 CC> > Cud 0.25 0.25 0.50 CC> > O 0.00 0.00 0.00 CC> > O 0.50 0.00 0.00 CC> > O 0.00 0.50 0.00 CC> > O 0.50 0.50 0.00 CC> > O 0.00 0.00 0.50 CC> > O 0.50 0.00 0.50 CC> > O 0.00 0.50 0.50 CC> > O 0.50 0.50 0.50 CC> > K_POINTS automatic CC> > 8,8,4,1,1,1 CC> > CELL_PARAMETERS cubic CC> > 3.878393250 3.878393249 0.000000000 CC> > -3.878393249 3.878393250 0.000000000 CC> > 0.000000000 0.000000000 6.409031058 CC> > CC> > CC> > CC> > CC> > CC> CC> CC> -- ======================================================================= Axel Kohlmeyer akohlmey at cmm.chem.upenn.edu http://www.cmm.upenn.edu Center for Molecular Modeling -- University of Pennsylvania Department of Chemistry, 231 S.34th Street, Philadelphia, PA 19104-6323 tel: 1-215-898-1582, fax: 1-215-573-6233, office-tel: 1-215-898-5425 ======================================================================= If you make something idiot-proof, the universe creates a better idiot.
