* Crystalline nickel [#fb6fa957]
This tutorial explains how to perform a spin-polarized calculation and how to perform the electronic structure analysis.
** SCF calculation [#x124bd13]
To calculate a system with spin polarization, one needs to set NSPIN=2 and nonzero initial magnetizatin (ZETA1). With this input file, densities of states projected onto the atomic orbitals (AO_LDOS or PDOS) are printed in the output file.
- Input file (nfinp_scf)
  0  0  0  0  0  0
  5.00  15.00 1   1   1                : GMAX, GMAXP, NTYP, NATM, NATM2
  225   2                              : num_space_group, type
  6.70  6.700  6.700 90.00 90.00 90.00 : a,b,c,alpha,beta,gamma
  16  16  16  1   1   1                : K_mesh
  0   0                                : NCORD, NINV,   : IWEI, IMDTYP, ITYP
  0.00  0.00   0.00  1  0  1           : CPS(1,1:3) IWEI IMDTYP ITYP
  28    0.50   58.69 6  1  0.1         : IATOMN,ALFA,AMION,ILOC,IVAN ZETA1
  0  0  0  0  0                        : ICOND INIPOS INIVEL ININOS INIACC
  0  1                                 : IPRE IPRI
  30 30    0  84200.00  0              : NMD1 NMD2 LAST_ITER CPUMAX IFSTOP
  6  1                                 : WAY_MIX MIX_WHAT
  0  20 0.30                           : ITER_START KBXMIX MIX_ALPHA
  0.20  0.30  0.20  0.20  0.20         : DTIM1 DTIM2 DTIM3 DTIM4 DTIM
  300.00   4  1     0.50D-09           : DTIO IMDALG IEXPL EDELTA
  -10.020  0.50D+03 0                  : WIDTH FORCCR ISTRESS
 ggapbe    2                           : XCTYPE KSPIN
  2.00                                 : DESTM
  102                                  : NBZTYP
  4    4    4                          : NKX NKY NKZ (DUMMY)
  4    4    4                          : NKX2 NKY2 NKZ2 (DUMMY)
  24                                   : KEG
  1                                    : NEXTST
  0                                    : (DUMMY)
  2                                    : IMSD
  0                                    : EVALUATE_EKO_DIFF
  1                                    : NPDOSAO
  1                                    : IPDOST
  -15.00  5.00  0.20   501             : EPDOS(1) EPDOS(2) EPDOS(3) NPDOSE
    2.40  0.20                         : RPDOS(1) RPDOS(2)
    0.20  14                           : DR NR
  0   0.00                             : DUMMY DUMMY

** Band structure calculation [#d091abe7]
After the SCF calculation, perform a non-SCF band structure calculation by setting ICOND=22 and high-symmetry k-points in the &KPOINTS_BAND...&END block
- nfinp_band
  0  0  0  0  0  0
  5.00  15.00 1   1   1                : GMAX, GMAXP, NTYP, NATM, NATM2
  225   2                              : num_space_group, type
  6.70  6.700  6.700 90.00 90.00 90.00 : a,b,c,alpha,beta,gamma
  16  16  16  1   1   1                : K_mesh
  0   0                                : NCORD, NINV,   : IWEI, IMDTYP, ITYP
  0.00  0.00   0.00  1  0  1           : CPS(1,1:3) IWEI IMDTYP ITYP
  28    0.50   58.69 6  1  0.1         : IATOMN,ALFA,AMION,ILOC,IVAN
  22 0  0  0  0                        : ICOND INIPOS INIVEL ININOS INIACC
  0  1                                 : IPRE IPRI
  30 30    0  84200.00  0              : NMD1 NMD2 LAST_ITER CPUMAX IFSTOP
  6  1                                 : WAY_MIX MIX_WHAT
  0  20 0.30                           : ITER_START KBXMIX MIX_ALPHA
  0.20  0.30  0.20  0.20  0.20         : DTIM1 DTIM2 DTIM3 DTIM4 DTIM
  300.00   4  1     0.50D-09           : DTIO IMDALG IEXPL EDELTA
  -10.020  0.50D+03 0                  : WIDTH FORCCR ISTRESS
 ggapbe    2                           : XCTYPE KSPIN
  2.00                                 : DESTM
  102                                  : NBZTYP
  4    4    4                          : NKX NKY NKZ (DUMMY)
  4    4    4                          : NKX2 NKY2 NKZ2 (DUMMY)
  24                                   : KEG
  1                                    : NEXTST
  0                                    : (DUMMY)
  2                                    : IMSD
  0                                    : EVALUATE_EKO_DIFF
  0                                    : NPDOSAO
  0   0.00                             : DUMMY DUMMY
 &KPOINTS_BAND
  NKSEG 4
  KMESH 40 20 20 20
  KPOINTS
  0.000 0.000 0.000
  0.000 0.500 0.500
  0.250 0.500 0.750
  0.500 0.500 0.500
  0.000 0.000 0.000
 &END
** Postprocessing [#gddd434d]
To plot the band strcture of a spin polarized system, perfrom the following
 > energy2band -s
and input the number of bands, the number of bands used to plot the band, the number of k-points, and the Fermi level. DO NOT remember to add the option "-s", which is necessary for the spin-polarized system. Then one obtain "band_up.data" and "band_dw.data", which can be used to plot the band structure using gnuplot, xmgrace, or alike. Here is an example of the gnuplot script
 set terminal postscript eps 'Helvetica' 22
 set output 'band.eps'
 emin=-10.0
 emax=10.0
 xmin=0.0
 xmax=2.88194910
 G=0.0
 X=0.93778885
 W=1.40668328
 L=2.06980013
 G2=2.88194910
 offset=0.75
 set xrange [xmin:xmax]
 set yrange [emin:emax]
 set key top left
 unset xtics
 unset xlabel
 set ylabel 'E-E_F (eV)'
 set xzeroaxis
 set arrow from X,emin to X,emax nohead
 set arrow from W,emin to W,emax nohead
 set arrow from L,emin to L,emax nohead
 set label '{/Symbol G}' at G,emin-offset center
 set label 'X' at X,emin-offset center
 set label 'W' at W,emin-offset center
 set label 'L' at L,emin-offset center
 set label '{/Symbol G}' at G2,emin-offset center
 plot 'band_up.data' using 1:2  with lines title 'Spin-up' lt 1 lw 3,     'band_dw.data' using 1:2  with lines title 'Spin-down' lt 2 lw 3

トップ   新規 一覧 単語検索 最終更新   ヘルプ   最終更新のRSS