Electronic Properties in WIEN2K

#1. Non-Magnetic Calculation

In this section, we will learn how to calculate non-magnetic electronic properties such electronic band structure and density of sates in Wien2K.

Step 1: Creating structure/input file i.e .struct file

Lets make a directory test

If you have or want to have different directory than me, then just replace test by name of your current directory. Note symbol '$' means it is command, run it on terminal.

Let's begin!

$ makdir test

$ cd test

$ makestruct_lapw ! while creating struct file I am taking TiN

Title: test

Spacegroup or lattice:L test

Lattice Type: F

Unit: A

Lattice length: 4.235

NEq atoms: 2

1st:Ni 0.0 0.0 0.0

2nd: N 0.5 0.5 0.5

RMT reduction:2 and then return: n

$ cp init.struct test.struct

If you have cif, you can do this also using $cif2struct test.cif

Step 2: Initialization of Caclulation. Important flags:rkmax, numk

Run the command

$ init_lapw -b -numk 5000 -vxc 13 -rkmax 6.0 -ecut -7.0

! or for new version of wien2k

$ init_lapw -b -hdlo -vxc 13 -ecut -7.0 -numk 1600 -rkmax 6.5 -lvns 6 -gmax 16.0 -fftfac 2.0

Step 3: Run the calculation

$ run_lapw -ec 0.0001 -cc 0.001 -NI

$ save_lapw -d pbe

$ clean_lapw

Step 4: Band structure

! get test.klist_band using xcryden

$ x lapw1 -band

$ x lapw2 -band -qtl

$ grepline :FER 'test.scf' 1

$ x spaghetti # it will create soc.insp file

! insert fermienergy for this:

$ vi test.insp

! look for x.xxxxxxxxxxxx and replace it by actual Fermi energy pressing key 'i'

press key 'Esc', then shift+; and type wq to save and close vi editor

$ x spaghetti

! plot the band structure with plotting tool

$ xmgrace test.bands.agr

$ save_lapw -band -d pbeband

Step 4: TDOS and PDOS calculation

$ vi test.in1 ! set larger value of Emax 3.0 (opional sometime)

$ x kgen ! Set denser k-mesh

$ x lapw1 ! steps 1-3 are not required for direct dos calculation after scf run and start from 4 but remember if you are calculating after band calculation do steps 1-3.

$ x lapw2 -qtl

$ configure_int_lapw ! select different orbitals

$ x tetra

$ dosplot2_lapw

$ save_lapw -dos -d pbedos

! Note that it is better to calculate DOS before band structure. If DOS is done first then we dont need steps 1 and 2 but if did it after band calculation then steps 1 and 2 are mandatory.

#2. Magnetic Calculation

In this section, we will learn how to calculate magnetic (Ferromagnetic) electronic properties such electronic band structure and density of sates in Wien2K. I am explaining by taking NiO as an example. I recomend to go trhough #1

Creating structure, Initialization, and SCF calculation

$ makdir NiO

$ cd NiO

$ makestruct_lapw !(L,F,A,4.186,2, Ni=0,0,0 and O=0.5,0,0)

$ cp init.struct NiO.struct

$ init_lapw -b -numk 5000 -vxc 13 -rkmax 6.0 -ecut -7.0 -sp

Note here -sp flag is for magnetic calculation

$ runsp_lapw -ec 0.00001 -cc 0.0001 -NI

$ save_lapw -d pbe_fm

$ clean_lapw

Band structure calculation

! get NiO.klist_band using xcryden

$ x lapw1 -band -up

$ x lapw1 -band -dn

$ x lapw2 -band -qtl -up

$ x lapw2 -band -qtl -dn

$ grepline :FER *.scf 1

$ x spaghetti -up # it will create soc.insp file

$ vi NiO.insp ! insert fermienergy into NiO.insp

$ x spaghetti -up

$ x spaghetti -dn

! plot the band structure with plotting tool

$ xmgrace NiO.bandsup.agr NiO.bandsdn.agr

$ save_lapw -band -d pbe

TDOS and PDOS calculation

$ vi NiO.in1

$ x kgen ! Set denser k-mesh optional

$ x lapw1 -up -p ! optional but do once if you are doing after band calculation

$ x lapw1 -dn -p ! optional but do once if you are doing after band calculation

$ x lapw2 -up -qtl -p

$ x lapw2 -dp -qtl -p

$ configure_init_lapw ! select different orbitals

$ x tetra -up -p

$ x tetra -dn -p

$ dosplot2 -up ! chose for dn too

$ save_lapw -dos -d pbe

! Note that it is better to calculate DOS before band structure. If DOS is done first then we dont need steps 1 and 2 but if done after band calculation then steps 1 and 2 are mandatory.

#3. Inclusion of SOC (Non-magnetic)

Creating structure, Initialization, and Running calculation

! Note that just remove -p flag for non-parallel calculation.

$ makdir soc

$ cd soc

$ makestruct_lapw

$ cp init.struct soc.struct

$ init_lapw -b -numk 5000 -vxc 13 -rkmax 6.0 -ecut -7.0

$ run_lapw -p -ec 0.00001 -cc 0.0001 -NI

$ save_lapw -d pbensco

$ initso_lapw

! Note set magnetisation along 0 0 1 direction and continue set up with default initialisation and spin-polarisation N.

! Increase Emax in soc.in1

$ run_lapw -p -so -ec 0.00001 -cc 0.0001 -NI

$ save_lapw -d pbesoc

SOC band structure calculation

! get soc.klist_band

$ x lapw1 -band -p

$ x lapwso -p

$ x lapw2 -band -qtl -so -p

$ grepline :FER *.scf 1

$ x spaghetti -p -so # it will create soc.insp file

! insert fermienergy into soc.insp

$ x spaghetti -p -so

! plot the band structure with plotting tool

$ xmgrace soc.bands.agr

$ save_lapw -band -d socband

SOC TDOS and PDOS calculation

$ vi test.in1 ! set larger emax around 3

$ x kgen -p -so ! set denser k-mesh

$ x lapw1 -p

$ x lapwso -p

$ x lapw2 -so -qtl -p

$ x tetra -so -p

$ configure_init_lapw

$ x tetra -so -p

$ dosplot_lapw

$ save_lapw -dos -d socdos

! Note that it is better to calculate DOS before band structure. If DOS is done first then we dont need steps 1 and 2 but if done after band calculation then steps 1 and 2 are mandatory.

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