Top Page > Browsing
What will the value of "NEGF.Channel.Num" for eigen channel calculation in AGNR.
Date: 2020/09/11 19:09
Name: Lovleen Kaur   <lovleenkaurkkr@gmail.com>

I am trying to compute electron transport properties of armchair graphene nanoribbon (AGNR). I am interested in computing the eigen channels that are responsible for conductance of the ribbon at a particular voltage. In the input file there is a parameter named "NEGF.Channel.Num", i want to know that which value should be assigned to this in the case of AGNR. Defaults values are 5 and 10. Can i change it to 1.
The input file is as follows:
#
#
# File Name

System.CurrrentDirectory ./ # default=./
System.Name NEGF-Graphene
DATA.PATH ../../../../../../../DFT_DATA13
level.of.stdout 1 # default=1 (1-3)
level.of.fileout 1 # default=1 (0-2)


NEGF.filename.hks.l ../graphene-l.hks
NEGF.filename.hks.r ../graphene-r.hks

NEGF.Num.Poles 100 # defalut=150
NEGF.scf.Kgrid 1 1 # defalut=1 1

NEGF.bias.voltage 0.0 # default=0.0 (eV)
NEGF.bias.neq.im.energy 0.01 # default=0.01 (eV)
NEGF.bias.neq.energy.step 0.02 # default=0.02 (eV)

Dos.fileout off # on|off, default=off
NEGF.Dos.energyrange -15.0 25.0 5.0e-3 #default=-10.0 10.0 5.0e-3 (eV)
NEGF.Dos.energy.div 200 # default=200
NEGF.Dos.Kgrid 600 1 # default=1 1
NEGF.SCF.Iter.Band 20

#
# Transmission & Eigen Channel
#

NEGF.tran.Analysis on # default on
NEGF.tran.energydiv 200 # default=200
NEGF.tran.energyrange -10.0 10.0 1.0e-3 # default=-10.0 10.0 1.0e-3 (eV)
NEGF.tran.Kgrid 1 1 # default= 1 1
NEGF.tran.Channel on # default on
NEGF.Channel.Nkpoint 1 # default=1
<NEGF.Channel.kpoint
0.0 0.0
NEGF.Channel.kpoint>
# default 0.0 0.0
NEGF.Channel.Nenergy 1 # default=1
<NEGF.Channel.energy
0.0
NEGF.Channel.energy>
# default 0.0
NEGF.Channel.Num 5 # defualt=5(for collinear), 10(for Non-collinear)


#
# Definition of Atomic Species
#

Species.Number 2
<Definition.of.Atomic.Species
C C5.0-s2p1 C_PBE13
H H5.0-s1 H_PBE13
Definition.of.Atomic.Species>

#
# Atoms
#

Atoms.Number 110
Atoms.SpeciesAndCoordinates.Unit Ang # Ang|AU
<Atoms.SpeciesAndCoordinates
1 C 0.75309 1.25792 -0.00217 2.0 2.0
2 C 2.12851 1.25792 -0.00217 2.0 2.0
3 C 5.05574 1.25792 -0.00217 2.0 2.0
4 C 9.35840 1.25792 -0.00217 2.0 2.0
5 C 6.43116 1.25792 -0.00217 2.0 2.0
6 C 10.73382 1.25792 -0.00217 2.0 2.0
7 C 0.01233 2.46212 -0.00217 2.0 2.0
8 C 0.00406 4.93461 -0.00217 2.0 2.0
9 C 0.00406 7.39586 -0.00217 2.0 2.0
10 C 0.01233 9.86835 -0.00217 2.0 2.0
11 C 2.86926 2.46212 -0.00217 2.0 2.0
12 C 2.87753 4.93461 -0.00217 2.0 2.0
13 C 2.87753 7.39586 -0.00217 2.0 2.0
14 C 2.86926 9.86835 -0.00217 2.0 2.0
15 C 0.72401 3.69376 -0.00217 2.0 2.0
16 C 0.72069 6.16524 -0.00217 2.0 2.0
17 C 0.72401 8.63671 -0.00217 2.0 2.0
18 C 0.75309 11.07255 -0.00217 2.0 2.0
19 C 2.15759 3.69376 -0.00217 2.0 2.0
20 C 2.16090 6.16524 -0.00217 2.0 2.0
21 C 2.15759 8.63671 -0.00217 2.0 2.0
22 C 2.12851 11.07255 -0.00217 2.0 2.0
23 C 4.31499 2.46212 -0.00217 2.0 2.0
24 C 4.30672 4.93461 -0.00217 2.0 2.0
25 C 4.30672 7.39586 -0.00217 2.0 2.0
26 C 4.31499 9.86835 -0.00217 2.0 2.0
27 C 8.61765 2.46212 -0.00217 2.0 2.0
28 C 8.60938 4.93461 -0.00217 2.0 2.0
29 C 8.60938 7.39586 -0.00217 2.0 2.0
30 C 8.61765 9.86835 -0.00217 2.0 2.0
31 C 7.17192 2.46212 -0.00217 2.0 2.0
32 C 7.18019 4.93461 -0.00217 2.0 2.0
33 C 7.18019 7.39586 -0.00217 2.0 2.0
34 C 7.17192 9.86835 -0.00217 2.0 2.0
35 C 11.47457 2.46212 -0.00217 2.0 2.0
36 C 11.48284 4.93461 -0.00217 2.0 2.0
37 C 11.48284 7.39586 -0.00217 2.0 2.0
38 C 11.47457 9.86835 -0.00217 2.0 2.0
39 C 5.02666 3.69376 -0.00217 2.0 2.0
40 C 5.02335 6.16523 -0.00217 2.0 2.0
41 C 5.02666 8.63671 -0.00217 2.0 2.0
42 C 5.05574 11.07255 -0.00217 2.0 2.0
43 C 9.32932 3.69376 -0.00217 2.0 2.0
44 C 9.32600 6.16524 -0.00217 2.0 2.0
45 C 9.32932 8.63671 -0.00217 2.0 2.0
46 C 9.35840 11.07255 -0.00217 2.0 2.0
47 C 6.46024 3.69376 -0.00217 2.0 2.0
48 C 6.46356 6.16524 -0.00217 2.0 2.0
49 C 6.46024 8.63671 -0.00217 2.0 2.0
50 C 6.43116 11.07255 -0.00217 2.0 2.0
51 C 10.76290 3.69376 -0.00217 2.0 2.0
52 C 10.76622 6.16524 -0.00217 2.0 2.0
53 C 10.76290 8.63671 -0.00217 2.0 2.0
54 C 10.73382 11.07255 -0.00217 2.0 2.0
55 H 0.23717 0.29989 -0.00217 0.5 0.5
56 H 2.64442 0.29989 -0.00217 0.5 0.5
57 H 4.53983 0.29989 -0.00217 0.5 0.5
58 H 6.94708 0.29989 -0.00217 0.5 0.5
59 H 8.84249 0.29989 -0.00217 0.5 0.5
60 H 11.24974 0.29989 -0.00217 0.5 0.5
61 H 11.24974 12.03058 -0.00217 0.5 0.5
62 H 8.84249 12.03058 -0.00217 0.5 0.5
63 H 6.94708 12.03058 -0.00217 0.5 0.5
64 H 4.53983 12.03058 -0.00217 0.5 0.5
65 H 2.64442 12.03058 -0.00217 0.5 0.5
66 H 0.23717 12.03058 -0.00217 0.5 0.5
67 C 13.66106 1.25792 -0.00217 2.0 2.0
68 C 15.03648 1.25792 -0.00217 2.0 2.0
69 C 17.96372 1.25792 -0.00217 2.0 2.0
70 C 19.33914 1.25792 -0.00217 2.0 2.0
71 C 12.92031 2.46212 -0.00217 2.0 2.0
72 C 12.91204 4.93461 -0.00217 2.0 2.0
73 C 12.91204 7.39586 -0.00217 2.0 2.0
74 C 12.92031 9.86835 -0.00217 2.0 2.0
75 C 15.77723 2.46212 -0.00217 2.0 2.0
76 C 15.78550 4.93461 -0.00217 2.0 2.0
77 C 15.78550 7.39586 -0.00217 2.0 2.0
78 C 15.77723 9.86835 -0.00217 2.0 2.0
79 C 13.63198 3.69376 -0.00217 2.0 2.0
80 C 13.62866 6.16524 -0.00217 2.0 2.0
81 C 13.63198 8.63671 -0.00217 2.0 2.0
82 C 13.66106 11.07255 -0.00217 2.0 2.0
83 C 15.06556 3.69376 -0.00217 2.0 2.0
84 C 15.06888 6.16524 -0.00217 2.0 2.0
85 C 15.06556 8.63671 -0.00217 2.0 2.0
86 C 15.03648 11.07255 -0.00217 2.0 2.0
87 C 17.22296 2.46212 -0.00217 2.0 2.0
88 C 17.21470 4.93461 -0.00217 2.0 2.0
89 C 17.21470 7.39586 -0.00217 2.0 2.0
90 C 17.22296 9.86835 -0.00217 2.0 2.0
91 C 20.07989 2.46212 -0.00217 2.0 2.0
92 C 20.08816 4.93461 -0.00217 2.0 2.0
93 C 20.08816 7.39586 -0.00217 2.0 2.0
94 C 20.07989 9.86835 -0.00217 2.0 2.0
95 C 17.93464 3.69376 -0.00217 2.0 2.0
96 C 17.93132 6.16524 -0.00217 2.0 2.0
97 C 17.93464 8.63671 -0.00217 2.0 2.0
98 C 17.96372 11.07255 -0.00217 2.0 2.0
99 C 19.36822 3.69376 -0.00217 2.0 2.0
100 C 19.37153 6.16523 -0.00217 2.0 2.0
101 C 19.36822 8.63671 -0.00217 2.0 2.0
102 C 19.33914 11.07255 -0.00217 2.0 2.0
103 H 13.14515 0.29989 -0.00217 0.5 0.5
104 H 15.55239 0.29989 -0.00217 0.5 0.5
105 H 17.44780 0.29989 -0.00217 0.5 0.5
106 H 19.85505 0.29989 -0.00217 0.5 0.5
107 H 19.85505 12.03058 -0.00217 0.5 0.5
108 H 17.44780 12.03058 -0.00217 0.5 0.5
109 H 15.55239 12.03058 -0.00217 0.5 0.5
110 H 13.14515 12.03058 -0.00217 0.5 0.5
Atoms.SpeciesAndCoordinates>

#
# Lead-Left
#

LeftLeadAtoms.Number 22
<LeftLeadAtoms.SpeciesAndCoordinates
1 C -2.174100 1.257900 -0.00217 2.0 2.0
2 C -1.433400 2.462100 -0.00217 2.0 2.0
3 C -2.145100 3.693800 -0.00217 2.0 2.0
4 C -1.425100 4.934600 -0.00217 2.0 2.0
5 C -2.141700 6.165200 -0.00217 2.0 2.0
6 C -1.425100 7.395900 -0.00217 2.0 2.0
7 C -2.145100 8.636700 -0.00217 2.0 2.0
8 C -1.433400 9.868300 -0.00217 2.0 2.0
9 C -2.174100 11.07250 -0.00217 2.0 2.0
10 C -3.549500 1.257900 -0.00217 2.0 2.0
11 C -4.290300 2.462100 -0.00217 2.0 2.0
12 C -3.587700 3.693800 -0.00217 2.0 2.0
13 C -4.298600 4.934600 -0.00217 2.0 2.0
14 C -3.581900 6.165200 -0.00217 2.0 2.0
15 C -4.298600 7.395900 -0.00217 2.0 2.0
16 C -3.578700 8.636700 -0.00217 2.0 2.0
17 C -4.290300 9.868300 -0.00217 2.0 2.0
18 C -3.549500 11.07250 -0.00217 2.0 2.0
19 H -1.658200 0.299900 -0.00217 0.5 0.5
20 H -4.065500 0.299900 -0.00217 0.5 0.5
21 H -1.658200 12.03060 -0.00217 0.5 0.5
22 H -4.065500 12.03060 -0.00217 0.5 0.5
LeftLeadAtoms.SpeciesAndCoordinates>


#
# Lead-Right
#

RightLeadAtoms.Number 22
<RightLeadAtoms.SpeciesAndCoordinates
1 C 22.266300 1.257900 -0.00217 2.0 2.0
2 C 21.525600 2.462100 -0.00217 2.0 2.0
3 C 22.237300 3.693800 -0.00217 2.0 2.0
4 C 21.517400 4.934600 -0.00217 2.0 2.0
5 C 22.233900 6.165200 -0.00217 2.0 2.0
6 C 21.517400 7.395900 -0.00217 2.0 2.0
7 C 22.237300 8.636700 -0.00217 2.0 2.0
8 C 21.525600 9.868300 -0.00217 2.0 2.0
9 C 22.266300 11.07250 -0.00217 2.0 2.0
10 C 23.641700 1.257900 -0.00217 2.0 2.0
11 C 24.382500 2.462100 -0.00217 2.0 2.0
12 C 23.670900 3.693800 -0.00217 2.0 2.0
13 C 24.390900 4.934600 -0.00217 2.0 2.0
14 C 23.674100 6.165200 -0.00217 2.0 2.0
15 C 24.390900 7.395900 -0.00217 2.0 2.0
16 C 23.670900 8.636700 -0.00217 2.0 2.0
17 C 24.382500 9.868300 -0.00217 2.0 2.0
18 C 23.641700 11.07250 -0.00217 2.0 2.0
19 H 21.750400 0.299900 -0.00217 0.5 0.5
20 H 24.157600 0.299900 -0.00217 0.5 0.5
21 H 21.750400 12.03060 -0.00217 0.5 0.5
22 H 24.157600 12.03060 -0.00217 0.5 0.5
RightLeadAtoms.SpeciesAndCoordinates>




#
# SCF or Electronic System
#

scf.XcType GGA-PBE # LDA|LSDA-CA|LSDA-PW|GGA-PBE
scf.SpinPolarization on # On|Off|NC
scf.ElectronicTemperature 300.0 # default=300 (K)
scf.energycutoff 250.0 # default=150 (Ry)
scf.maxIter 200 # default=40
scf.EigenvalueSolver NEGF # DC|GDC|Cluster|Band
scf.lapack.dste dstevx # dstegr|dstedc|dstevx, default=dstegr
scf.Kgrid 1 1 1 # means n1 x n2 x n3
scf.Mixing.Type rmm-diisk # Simple|Rmm-Diis|Gr-Pulay|Kerker|Rmm-Diisk
scf.Init.Mixing.Weight 0.30 # default=0.30
scf.Min.Mixing.Weight 0.001 # default=0.001
scf.Max.Mixing.Weight 0.40 # default=0.40
scf.Mixing.History 5 # default=5
scf.Mixing.StartPulay 6 # default=6
#scf.Kerker.factor 1.0 # default=1.0
scf.criterion 1.0e-6 # default=1.0e-6 (Hartree)





Thanks

Regards,
Lovleen Kaur
メンテ
Page: [1]

Re: What will the value of "NEGF.Channel.Num" for eigen channel calculation in AGNR. ( No.1 )
Date: 2020/09/13 22:10
Name: Mitsuaki Kawamura  <mkawamura@issp.u-tokyo.ac.jp>

Dear Kaur

As written in the mannual,
http://www.openmx-square.org/openmx_man3.9/node133.html
> It specifies the number of eigenchannels that are printed in the real space representation. In each ${\bf k}$, energy, spin, NEGF.Channel.Num eigenchannels in descending order about transmission eigenvalues are printed in the Gaussian cube format; the real and imaginary part is printed separately.

If you specify as
NEGF.Channel.Num 1
you will get one eigenchannel that has the largest eigen-transmittance.

Best regards,
Mitsuaki Kawamura (ISSP)
メンテ

Page: [1]

Thread Title (must) Move the thread to the top
Your Name (must)
E-Mail (must)
URL
Password (used in modification of the submitted text)
Comment (must)

   Save Cookie