ngkpt and shiftk set from kptrlat
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roginovicci
- Posts: 75
- Joined: Thu Dec 02, 2010 10:36 pm
ngkpt and shiftk set from kptrlat
Dear all, could you please help me to calculate ngkpt variable and shiftk vectors for tetragonal bodycentered primitive cell. I found the kptrlat variable for the sctructure: kptrlatt 4 0 0 0 4 0 -2 -2 4 But for Response function calculation I need to know ngkpt vector. Is there any tutorial to convert kptrlat to ngkpt and shiftk. Thank you!
Re: ngkpt and shiftk set from kptrlat
Just use ngkpt and shiftk, don't use kptrlatt (that is, choose an ngkpt that will give the k point density you need, you can use prtkpt 1 to examine possibilities). This may not be quite as efficient as some of the other kptrlatt possibilities but makes life easier with the rsp fnc code.
Josef W. Zwanziger
Professor, Department of Chemistry
Canada Research Chair in NMR Studies of Materials
Dalhousie University
Halifax, NS B3H 4J3 Canada
jzwanzig@gmail.com
Professor, Department of Chemistry
Canada Research Chair in NMR Studies of Materials
Dalhousie University
Halifax, NS B3H 4J3 Canada
jzwanzig@gmail.com
-
roginovicci
- Posts: 75
- Joined: Thu Dec 02, 2010 10:36 pm
Re: ngkpt and shiftk set from kptrlat
Dear Prof. Josef,
I do appreciated a much for your answer! I'm kinda new in abinitio calculations, thus sorry for my newbie questions. I don't know the way how to find kpt grid for the structure. I have read the paper H. J. Monkhorst et al in Phys. Rev. (1976), but did not found the way how to find right kpt grid for the selected structure. For the above mentioned task I've used abinit with prtkpt=0 or 1 in input file and it prints the all possible grids (that's what you was saying?). For the tetragonal body centered structure it gives the following grids:
In the list there is no grid with diagonal kptrlat. Is there any reference book with list of grids for selected tetragonal structure? Is it the case I can always use the following grids:
1. ngkpt 4 4 4 shiftk 0 0 0.5
2. ngkpt 5 5 5 shiftk 0 0 0.5
3. ngkpt 6 6 6 shiftk 0 0 0.5
I do appreciated a much for your answer! I'm kinda new in abinitio calculations, thus sorry for my newbie questions. I don't know the way how to find kpt grid for the structure. I have read the paper H. J. Monkhorst et al in Phys. Rev. (1976), but did not found the way how to find right kpt grid for the selected structure. For the above mentioned task I've used abinit with prtkpt=0 or 1 in input file and it prints the all possible grids (that's what you was saying?). For the tetragonal body centered structure it gives the following grids:
Code: Select all
.Starting date : Sun 5 Jun 2011.
- ( at 19h25 )
- input file -> hg2cl2_opt.in
- output file -> hg2cl2_opt.outA
- root for input files -> hg2cl2_opt_1i
- root for output files -> hg2cl2_opt_1o
testkgrid : will perform the analysis of a series of k-grids.
Note that kptopt=1 in this analysis, irrespective of its input value.
Grid# kptrlatt shiftk kptrlen nkpt iset
1 1 1 0 5.0000E-01 1.1912E+01 1 1
-1 1 0 5.0000E-01
0 0 1 5.0000E-01
2 1 1 0 5.0000E-01 1.1973E+01 1 1
-1 1 0 5.0000E-01
0 0 2 5.0000E-01
3 2 2 0 5.0000E-01 2.3825E+01 4 1
-2 2 0 5.0000E-01
0 0 2 5.0000E-01
4 2 2 0 5.0000E-01 2.3945E+01 6 1
-2 2 0 5.0000E-01
0 0 3 5.0000E-01
5 3 3 0 5.0000E-01 3.5737E+01 14 1
-3 3 0 5.0000E-01
0 0 3 5.0000E-01
6 3 3 0 5.0000E-01 3.5918E+01 18 1
-3 3 0 5.0000E-01
0 0 4 5.0000E-01
7 4 4 0 5.0000E-01 4.7650E+01 32 1
-4 4 0 5.0000E-01
0 0 4 5.0000E-01
8 4 4 0 5.0000E-01 4.7891E+01 40 1
-4 4 0 5.0000E-01
0 0 5 5.0000E-01
9 5 5 0 5.0000E-01 5.9562E+01 63 1
-5 5 0 5.0000E-01
0 0 5 5.0000E-01
10 5 5 0 5.0000E-01 5.9863E+01 75 1
-5 5 0 5.0000E-01
0 0 6 5.0000E-01
11 6 6 0 5.0000E-01 7.1475E+01 108 1
-6 6 0 5.0000E-01
0 0 6 5.0000E-01
12 2 2 0 5.0000E-01 2.3825E+01 4 2
-2 2 0 5.0000E-01
0 0 2 5.0000E-01
13 2 2 0 5.0000E-01 2.3945E+01 8 2
-2 2 0 5.0000E-01
0 0 4 5.0000E-01
14 4 4 0 5.0000E-01 4.7650E+01 32 2
-4 4 0 5.0000E-01
0 0 4 5.0000E-01
15 4 4 0 5.0000E-01 4.7891E+01 48 2
-4 4 0 5.0000E-01
0 0 6 5.0000E-01
16 6 6 0 5.0000E-01 7.1475E+01 108 2
-6 6 0 5.0000E-01
0 0 6 5.0000E-01
17 -2 0 1 5.0000E-01 1.6889E+01 5 3
2 0 1 5.0000E-01
0 2 -1 5.0000E-01
18 -2 0 2 5.0000E-01 2.3825E+01 7 3
2 0 2 5.0000E-01
0 2 -2 5.0000E-01
19 -4 0 2 5.0000E-01 3.3779E+01 22 3
4 0 2 5.0000E-01
0 4 -2 5.0000E-01
20 -4 0 3 5.0000E-01 3.9545E+01 33 3
4 0 3 5.0000E-01
0 4 -3 5.0000E-01
21 -6 0 3 5.0000E-01 5.0668E+01 67 3
6 0 3 5.0000E-01
0 6 -3 5.0000E-01
22 -6 0 4 5.0000E-01 5.5951E+01 87 3
6 0 4 5.0000E-01
0 6 -4 5.0000E-01
23 -8 0 4 5.0000E-01 6.7558E+01 148 3
8 0 4 5.0000E-01
0 8 -4 5.0000E-01
24 -4 0 2 5.0000E-01 3.3779E+01 22 4
4 0 2 5.0000E-01
0 4 -2 5.0000E-01
25 -4 0 4 5.0000E-01 4.7650E+01 42 4
4 0 4 5.0000E-01
0 4 -4 5.0000E-01
26 -8 0 4 5.0000E-01 6.7558E+01 148 4
8 0 4 5.0000E-01
0 8 -4 5.0000E-01
27 -1 1 1 0.0000E+00 1.1912E+01 3 5
1 1 1 0.0000E+00
0 2 0 0.0000E+00
28 -1 1 2 0.0000E+00 1.6932E+01 5 5
1 1 2 0.0000E+00
0 2 0 0.0000E+00
29 -2 2 2 0.0000E+00 2.3825E+01 14 5
2 2 2 0.0000E+00
0 4 0 0.0000E+00
30 -2 2 3 0.0000E+00 3.1472E+01 17 5
2 2 3 0.0000E+00
0 4 0 0.0000E+00
31 -3 3 3 0.0000E+00 3.5737E+01 34 5
3 3 3 0.0000E+00
0 6 0 0.0000E+00
32 -3 3 4 0.0000E+00 4.2901E+01 46 5
3 3 4 0.0000E+00
0 6 0 0.0000E+00
33 -4 4 4 0.0000E+00 4.7650E+01 78 5
4 4 4 0.0000E+00
0 8 0 0.0000E+00
34 -4 4 5 0.0000E+00 5.4537E+01 93 5
4 4 5 0.0000E+00
0 8 0 0.0000E+00
35 -5 5 5 0.0000E+00 5.9562E+01 141 5
5 5 5 0.0000E+00
0 10 0 0.0000E+00
36 -5 5 6 0.0000E+00 6.6271E+01 171 5
5 5 6 0.0000E+00
0 10 0 0.0000E+00
37 -2 2 2 0.0000E+00 2.3825E+01 14 6
2 2 2 0.0000E+00
0 4 0 0.0000E+00
38 -2 2 4 0.0000E+00 3.3864E+01 24 6
2 2 4 0.0000E+00
0 4 0 0.0000E+00
39 -4 4 4 0.0000E+00 4.7650E+01 78 6
4 4 4 0.0000E+00
0 8 0 0.0000E+00
40 -4 4 6 0.0000E+00 6.2943E+01 114 6
4 4 6 0.0000E+00
0 8 0 0.0000E+00
List of best grids, ordered by nkpt.
(stop at a value of kptrlen 20% larger than the target value).
(the merit factor will tend to one or two in 3 dimensions)
(and to one, two or four in 2 dimensions)
nkpt kptrlen grid# merit_factor
1 1.1973E+01 2 0.4110
4 2.3825E+01 3 0.8097
6 2.3945E+01 4 0.5480
14 3.5737E+01 5 0.7808
18 3.5918E+01 6 0.6165
32 4.7650E+01 7 0.8097
For target kptrlen= 3.0000E+01, the selected grid is number 5,
giving kptrlen= 3.5737E+01 with nkpt= 14
In the list there is no grid with diagonal kptrlat. Is there any reference book with list of grids for selected tetragonal structure? Is it the case I can always use the following grids:
1. ngkpt 4 4 4 shiftk 0 0 0.5
2. ngkpt 5 5 5 shiftk 0 0 0.5
3. ngkpt 6 6 6 shiftk 0 0 0.5