AkaiKKR(Machikaneyama)

93

Band structure of WSe2

Posted on : September 07, 2016 (Wed) 18:29:39

by DUONG, DINH LOC

Dear Akai-KKR admins,

I have try to calculate the band structure of bulk WSe2 but I failed to see the band gap of WSe2.

Below is my input file.

Is there any visualization program to see the input structure of Akai-kkr? I think it will be very useful to check it. I am afraid that the structure I put in can be wrong.

Thank you for all your help in advance.

With best wishes,
Loc Duong

For first scf calculation:
go WSe2-bulk_pot
#- brvtyp a c/a b/a alpha beta gamma ----------------#
#fcc 10.822 1.0 1.0 90.0 90.0 90.0#
trc 6.202080818 3.948811634 1 90 90 120
#3.2774481773 0.0000000000 0.0000000000
#-1.6387240887 2.8383533812 0.0000000000
#0.0000000000 0.0000000000 20.0000000000
#- edelt ewidth reltyp sdftyp magtyp record----------------------#
0.001 1.0 srals gga91 mag init
#- record outtyp bzqlty maxiter pmix ----------------------#
update h 500 0.02
#- ntyp -------------------------------------------------------#
2
c#- type ncmp rmt field lmx anclr conc -------------------#
c#Co 1 0 0 3 27 100.0
c#CrFe 2 0 0 3 24 60.0
c# 26 40.0
c#Al 1 0 0 2 13 100.0
W 1 0 0 3 74 100
Se 1 0 0 3 34 100
c#- natm -------------------------------------------------------#
6
c#- atmicx -------------------- atmtyp -------------------------#
c#0.25000 0.25000 0.25000 Co
c#0.75000 0.75000 0.75000 Co
c#0.00000 0.00000 0.00000 CrFe
c#0.50000 0.50000 0.50000 Al
#0 0.577351616 1.012589619 W
#0.499998752 0.288675808 1.523563373 Se
#0.499998752 0.288675808 0.50165858 Se
0.333333343a 0.666666687b 0.250000000c W
0.666666627a 0.333333313b 0.750000000c W
0.333333343a 0.666666687b 0.621100008c Se
0.666666627a 0.333333313b 0.378899992c Se
0.666666627a 0.333333313b 0.121100008c Se
0.333333343a 0.666666687b 0.878899992c Se
# 0 0.577349166 0.987202906 W
# 0.49999999 0.288674583 2.961608717 W
# 0 0.577349166 2.452608117 Se
# 0.49999999 0.288674583 1.496203505 Se
# 0.49999999 0.288674583 0.478202306 Se
# 0 0.577349166 3.470609316 Se
c------ The following types of inputs and their combination
c are also allowed.
c------ In those cases a, b, b mean primitive unit vectors
c and x, y, z mean conventionnal cell vectors along
c x, y, and z axses. Bare numbers indicate cartesian
c coordinate in the unit of lattice constant a.
c 1/2 1/2 1/2 Fe
c 0a 0b 0c Fe
c 0x 0y 0z Fe
c 1/2a 1/2b 1/2c Fe
c------------------------------------------------------------
c#----------------------- end input data -----------------------#
end

For spc calculation:
#----------------------- WSe2-mono ---------------------------#
#- calctyp file ----------------------------------------------#
spc WSe2-bulk_pot
#- brvtyp a c/a b/a alpha beta gamma ----------------#
#fcc 10.822 1.0 1.0 90.0 90.0 90.0#
trc 6.202080818 3.948811634 1 90 90 120
#3.2774481773 0.0000000000 0.0000000000
#-1.6387240887 2.8383533812 0.0000000000
#0.0000000000 0.0000000000 20.0000000000
#- edelt ewidth reltyp sdftyp magtyp record----------------------#
0.001 1.0 srals gga91 mag 2nd
#- record outtyp bzqlty maxiter pmix ----------------------#
quit h 500 0.02
#- ntyp -------------------------------------------------------#
2
c#- type ncmp rmt field lmx anclr conc -------------------#
c#Co 1 0 0 3 27 100.0
c#CrFe 2 0 0 3 24 60.0
c# 26 40.0
c#Al 1 0 0 2 13 100.0
W 1 0 0 3 74 100
Se 1 0 0 3 34 100
c#- natm -------------------------------------------------------#
6
c#- atmicx -------------------- atmtyp -------------------------#
c#0.25000 0.25000 0.25000 Co
c#0.75000 0.75000 0.75000 Co
c#0.00000 0.00000 0.00000 CrFe
c#0.50000 0.50000 0.50000 Al
#0 0.577351616 1.012589619 W
#0.499998752 0.288675808 1.523563373 Se
#0.499998752 0.288675808 0.50165858 Se
0.333333343a 0.666666687b 0.250000000c W
0.666666627a 0.333333313b 0.750000000c W
0.333333343a 0.666666687b 0.621100008c Se
0.666666627a 0.333333313b 0.378899992c Se
0.666666627a 0.333333313b 0.121100008c Se
0.333333343a 0.666666687b 0.878899992c Se
# 0 0.577349166 0.987202906 W
# 0.49999999 0.288674583 2.961608717 W
# 0 0.577349166 2.452608117 Se
# 0.49999999 0.288674583 1.496203505 Se
# 0.49999999 0.288674583 0.478202306 Se
# 0 0.577349166 3.470609316 Se
c------ The following types of inputs and their combination
c are also allowed.
c------ In those cases a, b, b mean primitive unit vectors
c and x, y, z mean conventionnal cell vectors along
c x, y, and z axses. Bare numbers indicate cartesian
c coordinate in the unit of lattice constant a.
c 1/2 1/2 1/2 Fe
c 0a 0b 0c Fe
c 0x 0y 0z Fe
c 1/2a 1/2b 1/2c Fe
c------------------------------------------------------------
#end
#c "end" means the end of input data
#c "end" is not necessary unless other data used only
#c for "spc" exist below.
#----k-vector for spc-----------#
300
0.0000000000 0.0000000000 0.0000000000
-0.3333300000 0.6666700000 0.0000000000
0.0000000000 0.5000000000 0.0000000000
0.3333300000 0.3333300000 0.0000000000
0.0000000000 0.0000000000 0.0000000000

99

[Re:06] Band structure of WSe2

Posted on : September 13, 2016 (Tue) 11:26:45

by DUONG, DINH LOC

Thank you so much Hitoshi.

I will try to do it.

With best wishes,
Loc

98

[Re:05] Band structure of WSe2

Posted on : September 12, 2016 (Mon) 17:53:36

by Hitoshi GOMI

Hello Loc Duong,

It may be better to insert some empty spheres (Z = 0) to the vacuum region. But not certain, because I have never tried to calculate the slab model.

Hitoshi

97

[Re:04] Band structure of WSe2

Posted on : September 09, 2016 (Fri) 13:07:44

by DUONG, DINH LOC

Hi Hitoshi,

Thank you so much for your help. Your input is working and the band gap is generated. I will try further to get better band structure.

In addition, I try to calculate monolayer WSe2 by removing one layer in the input (off course I should increase the vacuum size along z direction). However, I can not get a proper the band structure of monolayer.

Is it possible to use the package for slab model? Could you give me some hints to improve the data with slab model (e.g. mono WSe2)?

Thank you all your help again.

With best wishes,
Loc Duong

(The input file for monolayer:
For go:
c--------------------WSe2-from Hitoshi------------------------------------
go data/WSe2-mono_spin_orbit
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
hex 6.2021, 3.9488, , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.5 srals mjw mag init
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 4 200 0.02
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
W 1 1 0 2 74 100
Se 1 1 0 2 34 100
c------------------------------------------------------------
c natm
3
c------------------------------------------------------------
c atmicx atmtyp
1/3a 2/3b 1/4c W
2/3a 1/3b 0.3789c Se
2/3a 1/3b 0.1211c Se
c---------------------------------------------------------

for spc:
c--------------------WSe2-Hitoshi------------------------------------
spc data/WSe2-mono_spin_orbit
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
hex 6.2021, 3.9488, , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 0.9 srals mjw mag 2nd
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 8 200 0.02
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
W 1 1 0 2 74 100
Se 1 1 0 2 34 100
c------------------------------------------------------------
c natm
3
c------------------------------------------------------------
c atmicx atmtyp
1/3a 2/3b 1/4c W
2/3a 1/3b 0.3789c Se
2/3a 1/3b 0.1211c Se
c------------------------------------------------------------
300
0.0000000 0.0000000 0.0
0.0000000 0.5773503 0.0
0.3333333 0.5773503 0.0
0.0000000 0.0000000 0.0
0.0000000 0.0000000 0.5
0.0000000 0.5773503 0.5
0.3333333 0.5773503 0.5
0.0000000 0.0000000 0.5
c------------------------------------------------------------

96

[Re:03] Band structure of WSe2

Posted on : September 09, 2016 (Fri) 00:40:18

by Hitoshi GOMI

Hello Loc Duong,

ewidth may be too small for self-consistent calculation.
Please try the following input.

Hitoshi

c--------------------WSe2------------------------------------
go data/WSe2
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
hex 6.2021, 3.9488, , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.5 sra mjw nmag 2nd
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 4 200 0.02
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
W 1 1 0 2 74 100
Se 1 1 0 2 34 100
c------------------------------------------------------------
c natm
6
c------------------------------------------------------------
c atmicx atmtyp
1/3a 2/3b 1/4c W
2/3a 1/3b 3/4c W
1/3a 2/3b 0.6211c Se
2/3a 1/3b 0.3789c Se
2/3a 1/3b 0.1211c Se
1/3a 2/3b 0.8789c Se
c------------------------------------------------------------

c--------------------WSe2------------------------------------
spc data/WSe2
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
hex 6.2021, 3.9488, , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 0.9 sra mjw nmag 2nd
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 8 200 0.02
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
W 1 1 0 2 74 100
Se 1 1 0 2 34 100
c------------------------------------------------------------
c natm
6
c------------------------------------------------------------
c atmicx atmtyp
1/3a 2/3b 1/4c W
2/3a 1/3b 3/4c W
1/3a 2/3b 0.6211c Se
2/3a 1/3b 0.3789c Se
2/3a 1/3b 0.1211c Se
1/3a 2/3b 0.8789c Se
c------------------------------------------------------------
300
0.0000000 0.0000000 0.0
0.0000000 0.5773503 0.0
0.3333333 0.5773503 0.0
0.0000000 0.0000000 0.0
0.0000000 0.0000000 0.5
0.0000000 0.5773503 0.5
0.3333333 0.5773503 0.5
0.0000000 0.0000000 0.5
c------------------------------------------------------------

95

[Re:02] Band structure of WSe2

Posted on : September 08, 2016 (Thu) 15:46:16

by DUONG, DINH LOC

I make one more test with Si and it seems the band structure is quite good.

I have change the exchange-correlation of GaAs from mjw to gga91 and the band gap appears.

I think the result is strongly dependent on the exchange-correlation.

Still, I can not solve the issue with WSe2 even I have used the gga91 for band gap estimation.

Could you give me some hints on it?

With best wishes,
Loc

94

[Re:01] Band structure of WSe2

Posted on : September 08, 2016 (Thu) 14:49:24

by DUONG, DINH LOC

I have a test with the gaas example provided in the code. Still I can not get the band gap of gaas.

Could you give me some hints to solve this problem.

With many thanks,
Loc Duong

(This is the input file:
For first scf calcualtion----
c----------------------GaAs----------------------------------
go gaas_pot
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
fcc 10.684 , , , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.5 sra mjw mag 2nd
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 4 500 0.035
c------------------------------------------------------------
c ntyp
4
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Ga 1 1 0.0 2 31 100
As 1 1 0.0 2 33 100
Vc1 1 1 0.0 0 0 100
Vc2 1 1 0.0 0 0 100
c------------------------------------------------------------
c natm
4
c------------------------------------------------------------
c atmicx atmtyp
0 0 0 Ga
0.25 0.25 0.25 As
0.5 0.5 0.5 Vc1
0.75 0.75 0.75 Vc2
c------------------------------------------------------------

And for BSF calcualtion:
c----------------------GaAs----------------------------------
spc gaas_pot
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
fcc 10.684 , , , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 0.5 sra mjw mag 2nd
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 4 50 0.035
c------------------------------------------------------------
c ntyp
4
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Ga 1 1 0.0 2 31 100
As 1 1 0.0 2 33 100
Vc1 1 1 0.0 0 0 100
Vc2 1 1 0.0 0 0 100
c------------------------------------------------------------
c natm
4
c------------------------------------------------------------
c atmicx atmtyp
0 0 0 Ga
0.25 0.25 0.25 As
0.5 0.5 0.5 Vc1
0.75 0.75 0.75 Vc2
300
0.0 0.0 0.0
0.0 0.0 1.0
#1.0 1.0 1.0
#0.0 0.0 0.0
#0.5 0.5 0.5

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