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bader charges

Posted: Mon Oct 09, 2006 5:49 pm
by achar002
Hi

As suggested by Andri, I went to http://theory.cm.utexas.edu/vtsttools/bader/vasp.php and made the changes to Main.F file and recompiled vasp. I then used C paw_GGA and B_h paw_GGA on a C42B8 unit cell, HIGH precision FFT grid and got the following Bader charge analysis.

# X Y Z CHARGE MIN DIST
--- ------------ -------------- ------------
1 -6.2895 10.9028 5.0869 4.5737 0.4428
2 1.2435 0.687 5.0869 4.1683 0.4444
3 -3.8639 10.9279 5.0869 4.3935 0.3166
4 -1.1936 10.9202 5.0869 4.5274 0.3916
5 7.5701 0.0159 5.0869 3.9871 0.4162
6 3.7654 10.9245 5.0869 4.4351 0.3588
7 6.3195 0.7283 5.0869 4.1434 0.3751
8 8.8594 0.7038 5.0869 4.1114 0.4259
9 -1.2354 2.2663 5.0869 4.4797 0.3561
10 10.0411 4.3619 5.0869 4.4772 0.3741
11 -3.7619 6.5807 5.0869 3.9697 0.4018
12 -5.0545 8.766 5.0869 4.1434 0.3751
13 0.0354 2.9215 5.0869 4.097 0.4086
14 -2.508 7.2757 5.0869 4.6054 0.4059
15 -3.8664 9.5289 5.0869 4.5274 0.3916
16 1.2664 2.1472 5.0869 3.9438 0.4002
17 0.0488 4.3666 5.0869 4.4409 0.4033
18 -1.2504 6.6323 5.0869 4.529 0.3502
19 3.773 2.2186 5.0869 4.6054 0.4059
20 1.2296 6.5727 5.0869 4.097 0.4086
21 0.0215 8.8072 5.0869 4.1683 0.4444
22 6.2532 2.1658 5.0869 4.4859 0.3849
23 5.0884 4.3798 5.0869 4.0867 0.4026
24 3.7916 6.5748 5.0869 4.215 0.4443
25 8.9053 2.1282 5.0869 4.4556 0.4328
26 7.5757 4.4131 5.0869 4.4316 0.3376
27 5.0556 8.7905 5.0869 4.1114 0.4259
28 2.5154 2.8619 5.0869 4.529 0.3502
29 1.2162 5.1277 5.0869 4.5681 0.4281
30 -0.0014 7.347 5.0869 3.9438 0.4002
31 -1.1961 9.5213 5.0869 4.3925 0.3166
32 5.0269 2.9135 5.0869 3.9697 0.4018
33 3.8739 5.1324 5.0869 4.4772 0.3741
34 2.5004 7.2279 5.0869 4.4797 0.3561
35 1.2295 9.5463 5.0869 4.5737 0.4427
36 6.3393 5.0811 5.0869 4.5915 0.4119
37 5.0097 7.3661 5.0869 4.4556 0.4328
38 3.8246 9.5247 5.0869 4.5847 0.3588
39 10.1234 2.9195 5.0869 4.215 0.4443
40 8.8266 5.1145 5.0869 4.0867 0.4025
41 7.6618 7.3285 5.0869 4.4859 0.3848
42 6.3449 9.4784 5.0869 3.9871 0.4161
43 -2.5331 8.7893 5.0869 2.2304 0.1846
44 2.5203 8.7542 5.0869 2.1957 0.1848
45 6.3273 6.5992 5.0869 2.2801 0.1853
46 2.5422 4.3848 5.0869 2.2031 0.1901
47 -1.2772 5.1094 5.0869 2.2031 0.1901
48 7.5877 2.895 5.0869 2.2801 0.1853
49 3.7981 0.7049 5.0869 2.2304 0.1846
50 11.3947 0.7401 5.0869 2.1957 0.1848

It has 199.3691 electrons instead of 192 electrons. I guess it is including some of the core electons. The first 42 atoms are carbon and the last 8 boron atoms. If I use C paw_GGA and B paw_GGA I get zero charges on boron and the # of electrons is 192. Is there a way to correct this?

Thanks

Posted: Mon Oct 09, 2006 9:11 pm
by andri
The best you can do is, using the same input parameters (same INCAR, KPOINTS and simulation cell), to calculate the the electron density around a single C atom and then a single B atom. Then compare these number to whatever the Bader partitioning gave for each atom in the system of interest. The difference will give how many charge units have migrated to or from a particular atom.

If you suspect that the density distribution should be more uniform, then try our new executables. Or better yet, download the source from our CVS site and recompile it. See the latest Sticky version posting.