wannier插值能带拟合2
作者:互联网
1) Wannier function的构造及其物理含义
2) Wannier function的应用: GW计算能带结构绘制
Thanks to Xiegang Zhu
认识1:第一性原理计算是为了获得wannier函数,有了wannier函数后就可以不需要第一性原理,直接通过wannier函数得到电子结构,尤其是表面态信息。
认识2: num_wann,num_band, Projections参数设置
认识3:画能带时高对称性k点位置的确定,可在wannier90_band.gnu文件中找到
vi wannier90_band.gnu
set data style dots
set nokey
set xrange [0: 5.73583]
set yrange [-49.75490 :211.32533]
set arrow from 0.51430, -49.75490 to 0.51430, 211.32533 nohead
set arrow from 1.76040, -49.75490 to 1.76040, 211.32533 nohead
set arrow from 2.27470, -49.75490 to 2.27470, 211.32533 nohead
set arrow from 3.52080, -49.75490 to 3.52080, 211.32533 nohead
set arrow from 4.59941, -49.75490 to 4.59941, 211.32533 nohead
set arrow from 5.11371, -49.75490 to 5.11371, 211.32533 nohead
set xtics (" G " 0.00000," A " 0.51430," H " 1.76040," K " 2.27470," G " 3.52080," M " 4.59941," L " 5.11371," H " 5.73583)
plot "wannier90_band.dat"
#num_wann = 64 ! set to NBANDS by VASP
num_wann=8
【nm_bands数量必须大于num_wann数量,从计算的64条能带中选取8条(num_bands),对这8条轨道采用wannier函数投影(wannier函数是实空间的函数);exclude_bands不是必须的;Nbands必须大于num_wann,否则会存在误投影情形】
num_bands=8
# for GW uncomment
exclude_bands 9-64
Begin Projections
Si:sp3
End Projections
【 这是初始猜测轨道,必须有;对Si来说,1个硅sp3的共4条,两个硅原子8条;对于ScH3,Sc以spd计算,则一个Sc原子需1+3+5=9条轨道,一个氢原子1条轨道,所以一个分子式的ScH3需要9+3=12条轨道,一个单胞有两个分子式,则需要24条轨道,因此,
num_wann=24,
num_bands=30 !(大于24即可);
如下方式设置投影
Begin Projections
Sc:l=0;l=1;l=2
H: l=-0
End Projections】
dis_froz_max=9
dis_num_iter=1000
guiding_centres=true
网络摘录1:
http://emuch.net/html/201311/6573747.html
0.1 下载wannier90-1.2,并编译安装
在 http://www.wannier.org/download.html 下载
wannier90-1.2
修改make.sys
如果装了ifort编译器
LIBS = -lmkl_intel_lp64 -lmkl_sequential -lmkl_core
然后 make all
0.2 重新编译VASP
之后修改vasp
LIB = -L../vasp.5.lib -ldmy \
../vasp.5.lib/linpack_double.o \
../wannier90-1.2/libwannier.a $(SCA) (LAPACK)(LAPACK)(BLAS)
CPP = $(CPP_) -DMPI -DHOST=\"LinuxIFC\" -DIFC \
-DCACHE_SIZE=4000 -DPGF90 -Davoidalloc \
-DMPI_BLOCK=8000 -Duse_collective -DscaLAPACK -DNGZhalf -DVASP2WANNIER90
之后重新make
分五步计算
1. step1:静态计算
INCAR
ISMEAR = 0
SIGMA = 0.05
2.得到虚轨道(导带上方的空轨道)
INCAR
ISMEAR = 0
SIGMA = 0.05
ALGO = Exact
NBANDS = 64
LOPTICS=.TRUE.
NEDOS=2000
3. GW计算
INCAR
ALGO = GW0 ; LSPECTRAL = .TRUE. ; NOMEGA = 50
NBANDS=64
LRPA = .FALSE.
LWANNIER90=.TRUE.
前三步运行vasp 【第三步运行VASP前,需写好wannier90.win参数(可先不写wannier90.win文件,试运行在第三步运行VASP,自动产生符合POSCAR和KPOINTS的wannier90.win文件,再修改该文件,运行一遍VASP),以使得运行VASP后产生 wannier90.amn, wannier90.mmn, wannier90.eig三个文件,供后续第四步的wannier90.x程序调用】
4. step4:运行 wannier90.x wannier90
wannier90.win 【第三步运行完成之后得到的参数文件】
num_wann=8 【参数含义?】
num_bands=8
# for GW uncomment
exclude_bands 9-64
Begin Projections 【开始轨道投影?】
Si:sp3
End Projections
dis_froz_max=9
dis_num_iter=1000
guiding_centres=true
begin unit_cell_cart
2.7150000 2.7150000 0.0000000
0.0000000 2.7150000 2.7150000
2.7150000 0.0000000 2.7150000
end unit_cell_cart
begin atoms_cart
Si 0.0000000 0.0000000 0.0000000
Si 1.3575000 1.3575000 1.3575000
end atoms_cart
mp_grid = 4 4 4
begin kpoints
0.0000000 0.0000000 0.0000000
0.2500000 0.0000000 0.0000000
0.5000000 0.0000000 0.0000000
........
0.2500000 -0.5000000 -0.2500000
-0.2500000 0.2500000 -0.5000000
end kpoints
运行 wannier90.x wannier90
5.---step5:修改wannier90.win参数,再次运行 wannier90.x wannier90;能带即为wannier90_band.dat
num_wann=8
num_bands=8
# for GW uncomment
exclude_bands 9-64
Begin Projections
Si:sp3
End Projections
dis_froz_max=9
dis_num_iter=1000
guiding_centres=true
# Bandstructure plot
restart = plot
bands_plot = true
begin kpoint_path
L 0.50000 0.50000 0.5000 G 0.00000 0.00000 0.0000
G 0.00000 0.00000 0.0000 X 0.50000 0.00000 0.5000
X 0.50000 0.00000 0.5000 K 0.37500 -0.37500 0.0000
K 0.37500 -0.37500 0.0000 G 0.00000 0.00000 0.0000
end kpoint_path
bands_num_points 40
bands_plot_format gnuplot xmgrace
begin unit_cell_cart
2.7150000 2.7150000 0.0000000
0.0000000 2.7150000 2.7150000
2.7150000 0.0000000 2.7150000
end unit_cell_cart
begin atoms_cart
Si 0.0000000 0.0000000 0.0000000
Si 1.3575000 1.3575000 1.3575000
end atoms_cart
mp_grid = 4 4 4
begin kpoints
0.0000000 0.0000000 0.0000000
0.2500000 0.0000000 0.0000000
0.5000000 0.0000000 0.0000000
0.2500000 0.2500000 0.0000000
0.5000000 0.2500000 0.0000000
..........
0.2500000 -0.5000000 -0.2500000
-0.2500000 0.2500000 -0.5000000
end kpoints
再次运行 wannier90.x wannier90;能带即为wannier90_band.dat
如果你有gnuplot,可以直接执行wannier90_band.gnu。
标签:wannier90,num,插值,bands,wannier,0.2500000,2.7150000,0.0000000,拟合 来源: https://blog.csdn.net/bubu789/article/details/119220359