Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : September 07, 2018 (Fri) 22:23:24

by Qais Ali

Dear Hitoshi,
Thank you for your kind suggestions for converging the anti-ferromagnetic (afm) state of bcc and fcc Fe. I can converge the KKR calculations for afm structure of fcc-Fe but the total energy values are higher compared to fm and nm bcc-Fe than expected. Can you please tell that are the energy values biased in this case since I used Fixed Spin Moment? Can we say that total energy values are self-consistent for afm structures of Fe (fcc)? Looking forward to hear from you soon.

Regards,
Qais

[Re:18] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : May 10, 2019 (Fri) 05:40:14

by Qais Ali

Dear Hitoshi GOMI,
Your suggestions were helping a lot for AkaiKKR users like me. I can see a notification about renewal of AkaiKKR website, may I ask that until when we can expect your response to our queries?

Regards,
Qais

[Re:17] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : February 23, 2019 (Sat) 03:46:47

by Qais Ali

Dear Hitoshi GOMI,

Thank you for very helping comments and answers to my queries.
Related to FCC Fe calculations I made two files one with single atom with following input;
c------------------------------
go data/test_1
c brvtyp a c/a b/a alpha beta gamma
fcc 6.23,1,,,,,
c-----------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag init
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 3 300 0.035
c------------------------------------------------------------
c ntyp
1
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe1 1 0.35355 0.0 2
26 100
c------------------------------------------------------------
c natm
1
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0 0 0 Fe1
c-----------------------------------------------------------

And second file with four atoms as shown below;

c------------------------------
go data/test_4
c brvtyp a c/a b/a alpha beta gamma
sc 6.23,1,,,,,
c-----------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag init
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 3 300 0.035
c------------------------------------------------------------
c ntyp
4
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe1 1 0.35355 0.0 2
26 100
Fe2 1 0.35355 0.0 2
26 100
Fe3 1 0.35355 0.0 2
26 100
Fe4 1 0.35355 0.0 2
26 100
c------------------------------------------------------------
c natm
4
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0 0 0 Fe1
0.5 0 0.5 Fe2
0.5 0.5 0 Fe3
0 0.5 0.5 Fe4
c-----------------------------------------------------------

I expect that total energy per atom for both of these cases remains same, however, there exists an energy difference of ~62meV between them, so can you please identify mistake or the reason for this difference? I shall be thankful for your helpful reply.

Regards,
Qais Ali

[Re:16] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : January 17, 2019 (Thu) 01:57:38

by Hitoshi GOMI

Hello Qais,

Answer to the first question.

According to the Oxford English dictionary, "optimize" means:
"Make the best or most effective use of (a situation or resource)"
https://en.oxforddictionaries.com/definition/optimize

I simply mean that the touching value is not always the best.

---
Answer to the second question.

You have to FIX the percentage of the volume filling.
FIX means that you have to use the same percentage of the volume filling throughout a series of your calculations.

Note that the muffin-tin sphere cannot overlap with each other, so that 100 % is impossible.

Note also that the touching value changes with c/a, so that the touching value is not good for this purpose.

Hitoshi GOMI

[Re:15] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : January 17, 2019 (Thu) 00:37:08

by Qais Ali

Dear Hitoshi,

Thanks for your continuous support. I was calculating the rmt values for different c/a values according to the method you told. First I would like to ask about the difference between touching and optimized rmt values.
Secondly, in one of your comment you also mentioned that one needs to fix the "volume filling" of muffin tin sphere (in other words to calculate muffin tin radius for each c/a). I want to know that which value of volume filling (in % as written in output) is supposed to be correct in terms of reliability of energy values and their comparison ; the 100% or the one corresponding to touching rmt or the one corresponding to optimized rmt values?
Regards,
Qais

[Re:14] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : January 11, 2019 (Fri) 10:19:30

by Hitoshi GOMI

Hello Qais Ali,

As far as I know, AkaiKKR does not support the fixed local magnetic moment.

Hitoshi GOMI

[Re:13] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : January 11, 2019 (Fri) 05:56:22

by Qais Ali

Dear Hitoshi GOMI,

Thank you for your valuable suggestions and posting the deleted log again. This time I want to ask you that is it possible in AkaiKKR to specify the magnetic moments of individual atoms separately over a range of volume. If yes, then how can one do it? For example to specify the artificial magnetic moment values to atoms of a crystal structure in lower volumes where the structure is supposed to be non-magnetic.

Regards,
Qais Ali

[Re:12] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : December 10, 2018 (Mon) 20:46:21

by Hitoshi GOMI

Dear all,

KKR administrator send me the deleted log.

Regards,
Hitoshi GOMI


------------------------------------------------------------
Anti-Ferromagnetic (AFM) calculation for bcc and fcc-Fe
------------------------------------------------------------
Dear all,

I need your help to perform electronic structure calculation for bcc-Fe and fcc-Fe in anti-ferromagnetic state. I like to calculate the energy differences of anti-ferromagnetic and ferromagnetic bcc and fcc Fe.

My input files for bcc-Fe is following;

======================================================================
bcc-Fe
=======================================================================
c----------------------Fe------------------------------------
go data/fe
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
bcc 5.32 , , , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag init
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 4 100 0.035
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe 1 1 0.0 2
26 100
Fe2 1 1 0.0 2
26 100
c------------------------------------------------------------
c natm
2
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0a 0b 0c Fe
0.5a 0.5b 0.5c Fe2


============================================================

and for fcc-Fe is below;

========================================================================
fcc-Fe
=======================================================================
c----------------------Fe------------------------------------
go data/fe
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
fcc 5.32 , , , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag init
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 4 100 0.035
c------------------------------------------------------------
c ntyp
4
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe 1 1 0.0 2
26 100
Fe2 1 1 0.0 2
26 100
Fe3 1 1 0.0 2
26 100
Fe4 1 1 0.0 2
26 100
c--------------------------------------------------------
c natm
4
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0a 0b 0c Fe
0.5a 0.5b 0c Fe2
0.5a 0b 0.5c Fe3
0a 0.5b 0.5c Fe4
c------------------------------------------------------------

When the code starts to run then it does not put the atoms exactly to the position as specified by the input file. For example for bcc-Fe it shows following;

atoms in the unit cell
position= 0.00000000 0.00000000 0.00000000 type=Fe
position= 0.25000000 0.25000000 0.25000000 type=Fe2


and for fcc-Fe it shows following positions;

atoms in the unit cell
position= 0.00000000 0.00000000 0.00000000 type=Fe
position= 0.25000000 0.25000000 0.50000000 type=Fe2
position= 0.25000000 0.50000000 0.25000000 type=Fe3
position= 0.50000000 0.25000000 0.25000000 type=Fe4

Furthermore self-consistent iterations are also not converging for both cases and following warning also prompts to the screen during calculation;

***wrn in chklat...given rmt's conflict; reduced.

I therefore request to please suggest me correct method to perform calculation for anti-ferromagnetic state of bcc and fcc-Fe. I shall be thankful to you.





------------------------------------------------------------
[Re:01] Anti-Ferromagnetic (AFM) calculation for bcc and fcc-Fe
------------------------------------------------------------
Hello Qais Ali,

There are three problems to be solved.
(1) Atomic position
(2) Bravais lattice
(3) Initial potential

Let's consider the ferromagnetic bcc Fe and B2-like antiferromagnetic Fe.
Then, you can apply to the ferromagnetic fcc Fe and L10-like antiferromagnetic Fe.

(1) Atomic position
First, you have to understand the difference between "0.5 0.5 0.5 Fe2" and "0.5a 0.5b 0.5c Fe2" for the atomic positions.
The former is specified by the Cartesian coordinates, and the latter is the fractional coordinates.


(2) Bravais lattice
The crystal structure is specified by the combination of a Bravais lattice and a basis.
You set the bcc Bravais lattice; its primitive translation vectors are found in the output as
a=( -0.50000 0.50000 0.50000)
b=( 0.50000 -0.50000 0.50000)
c=( 0.50000 0.50000 -0.50000)

And you specified the basis with two Fe atoms, which is located at (0a 0b 0c) and (1/2a 1/2b 1/2c) in the fractional coordinates.
Therefore, the atomic position of Fe2 is 0.5a + 0.5b + 0.5c = (0.25 0.25 0.25) in the Cartesian coordinates.

I recomend you to use the sc (simple cubic) Bravais lattice and the Cartesian coordinates as follows.

c----------------------Fe------------------------------------
go data/B2AFMfe
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
sc 5.32 , , , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag 2nd
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 4 100 0.035
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe1 1 1 0.0 2
26 100
Fe2 1 1 0.0 2
26 100
c------------------------------------------------------------
c natm
2
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0 0 0 Fe1
0.5 0.5 0.5 Fe2
c------------------------------------------------------------

(3) Initial potential
By using the above input, you can calculate B2 Fe.
But it may becomes ferromagnetic.
To get the initial potential for anti-ferromagnetic Fe, you can refer the following thereads.
http://kkr.issp.u-tokyo.ac.jp/bbs/thread.php?id=258
http://kkr.issp.u-tokyo.ac.jp/bbs/thread.php?id=215
http://kkr.issp.u-tokyo.ac.jp/bbs/thread.php?id=115

Hitoshi GOMI




------------------------------------------------------------
[Re:02] Anti-Ferromagnetic (AFM) calculation for bcc and fcc-Fe
------------------------------------------------------------
Dear Hitoshi,

Thanks a lot for the very clear and quick response.

Now, I am able to run the 2 atoms bcc FM Fe with your suggested input file.

I also used fmg to create new potential that has AFM configuration as follows:

./data/Fe_fm 1 2
./data/Fe_afm 1 -2

Later, I changed my input file as like in below:

c---------------------Fe------------------------------------
go data/Fe_afm
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
sc 5.32 , , , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag 2nd
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 4 100 0.035
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe1 1 1 0.0 2
26 100
Fe2 1 1 0.0 2
26 100
c------------------------------------------------------------
c natm
2
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0 0 0 Fe1
0.5 0.5 0.5 Fe2
c------------------------------------------------------------


However, even if I start with AFM configured potential my calculations converge to 2 atoms down FM configuration.

Can you please give further feedbacks.

Thanks in advance,
Qais




------------------------------------------------------------
[Re:03] Anti-Ferromagnetic (AFM) calculation for bcc and fcc-Fe
------------------------------------------------------------
Hello Qais Ali,

Generally speaking, it is difficult to get the convergence of unstable state.
In this particular case, the fixed spin moment (fsm) mode may solve the problem.

Please try the following input with afm initial potential.
The last "0.0" is the bulk magnetic moment, which restrict the system non-magnetic.

Hitoshi GOMI

c---------------------Fe------------------------------------
fsm data/Fe_afm
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
sc 5.32 , , , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag 2nd
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 4 100 0.035
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe1 1 1 0.0 2
26 100
Fe2 1 1 0.0 2
26 100
c------------------------------------------------------------
c natm
2
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0 0 0 Fe1
0.5 0.5 0.5 Fe2
c------------------------------------------------------------
c moment
0.0
c------------------------------------------------------------

[Re:11] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : December 06, 2018 (Thu) 12:52:24

by Hitoshi GOMI

Hello Qais,

I guess your rmt value is not an optimized one, but just a touching one.
This is just a simple mathematics.

The distance between Fe1 (0 0 0) and Fe3 (0.5 0.5 0) is calculated to be d13 = sqrt(a^2 + a^2) / 2 / a = sqrt(2) / 2.
Simiraly, the distance between Fe1 and Fe2 (0.5 0 0.5c) is calculated to be d12 = sqrt(a^2 + (a * c/a)^2) / 2 / a = sqrt(1 + (c/a)^2) / 2.

If c/a = 1, d12 = d13. Therefore, the touching rmt = d12 / 2 = d13 / 2.
If c/a > 1, d12 > d13. Therefore, the touching rmt = d13 / 2.
If c/a < 1, d12 < d13. Therefore, the touching rmt = d12 / 2.

Hitoshi GOMI

[Re:10] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : December 05, 2018 (Wed) 22:35:31

by Qais Ali

Dear Hitoshi,

Thank you very much for providing helpful suggestions regarding "rmt" parameter. I am trying to optimize "rmt" value for different values of c/a and I have following query;

When c/a < 1:

For c/a = 0.6 and 0.72 I observe the optimized 'rmt' value is 0.29155 and 0.30806 respectively.

When c/a > or = 1:

For c/a = 1, 1.2 and 1.4 I observe the optimized rmt value is 0.35355.
So why does rmt value remains same for c/a equal or greater than 1 but it varies for c/a lower than 1. I would highly appreciate your comment about this.

Regards,
Qais

[Re:09] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : November 25, 2018 (Sun) 01:05:34

by Hitoshi GOMI

Hello Qais Ali,

You have to understand the meaning of "rmt=1".

Basically, the user have to set the muffin-tin radii manually.
But, if the rmt value is too large and the conflicts occur, the AkaiKKR package automatically reduce the rmt values. Obviously, the "rmt=1" is always too large.

In your sample, the rmt values are reduced to 0.35355. This is printed in the output as follows.

type of site
type=Fe1 rmt= 0.35355 field= 0.000 lmxtyp= 2
component= 1 anclr= 26. conc= 1.0000

In this case, the muffin-tin spheres are touching with each other.
Therefore, this is the maximum value for the rmt.
You can edit the rmt values in your input to fix it.

Hitoshi GOMI

[Re:08] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : November 24, 2018 (Sat) 23:28:02

by Qais Ali

Dear Hitoshi GOMI,
Thank you for providing your valuable suggestions. I have checked the output by using the fractional coordinates and I observed the same results for atomic positions and hence the energy values as you mentioned in the last reply. Ofcourse it is making calculations more convinient.

However, how may I fix the "volume filling" of the muffin-tin sphere or how to calculate the muffin-tin radius for each c/a ? Can you please elaborate the procedure a little bit? As far as I know we specify the muffin-tin sphere radius under the "rmt" parameter and for my calculations at different c/a ratios I kept rmt=1 in all cases.

Regards,
Qais

[Re:07] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : November 23, 2018 (Fri) 12:48:06

by Hitoshi GOMI

Hello Qais Ali,

Thank you for the summary of the procedure.

---
>Is this way of specifying the atomic positions in KKR code is correct or I need to make changes?

"0.5 0 0.7 Fe2" is okey.
But it is convenient to use the fractional coordinates.

0 0 0 Fe1
0.5 0 0.5c Fe2
0.5 0.5 0 Fe3
0 0.5 0.5c Fe4

These two methods give the same result.
The atomic positions are printed in the output as follows.

atoms in the unit cell
position= 0.00000000 0.00000000 0.00000000 type=Fe1
position= 0.50000000 0.00000000 0.70000000 type=Fe2
position= 0.50000000 0.50000000 0.00000000 type=Fe3
position= 0.00000000 0.50000000 0.70000000 type=Fe4

You can confirm.

---

However, it should be noted that if you want to compare the total energy as function of c/a, you have to fix the "volume filling" of the muffin-tin sphere.
In other words, you have to calculate the muffin-tin radius for each c/a.

Regards,
Hitoshi GOMI

[Re:06] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : November 22, 2018 (Thu) 04:35:29

by Qais Ali

Dear Hitoshi GOMI,

I want to make E-V plot for AFM fct-Fe. In this case I am also changing c/a ratio corresponding to volume values. However I am seeking clarification regarding position of atoms. I am using atomic positions according to fct as given below,

A 0 0 0
B 0.5 0.5 0
C 0 0.5 c/2*a
D 0.5 0 c/2*a


This makes my one of the input files as given below;
c-----------fcc_afm---------------------------------------
go data/fct_1p4
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
st 6 ,1.4, , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag init
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 2 300 0.015
c------------------------------------------------------------
c ntyp
4
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe1 1 1 0.0 2
26 100
Fe2 1 1 0.0 2
26 100
Fe3 1 1 0.0 2
26 100
Fe4 1 1 0.0 2
26 100
c------------------------------------------------------------
c natm
4
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0 0 0 Fe1
0.5 0 0.7 Fe2
0.5 0.5 0 Fe3
0 0.5 0.7 Fe4
c-----------------------------------------------------------
c moment
c 0.0
c------------------------------------------------------------

Is this way of specifying the atomic positions in KKR code is correct or I need to make changes?

Regards,
Qais

[Re:05] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : November 22, 2018 (Thu) 01:57:20

by Qais Ali

Dear KKR users,
As suggested to me by Mr. Hitoshi to summarize here about AFM calculation of Fe. Following is the procedure to be followed.

First you have to make an input file like given below;
c-----------------bcc-Fe-fm------------------------------
go data/fe_bcc_FM
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
sc 4.95 , , , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag init
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 5 150 0.015
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe1 1 1 0.0 2
26 100
Fe2 1 1 0.0 2
26 100
c------------------------------------------------------------
c natm
2
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0 0 0 Fe1
0.5 0.5 0.5 Fe2
c------------------------------------------------------------
c moment
c 0.0
c----------------------------------------------------------

After you achieve the convergence you have to make following changes in your input file
c-----------------bcc-Fe-fm------------------------------
fsm data/fe_bcc_AFM
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
sc 4.95 , , , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag 2nd
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 5 150 0.015
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe1 1 1 0.0 2
26 100
Fe2 1 1 0.0 2
26 100
c------------------------------------------------------------
c natm
2
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0 0 0 Fe1
0.5 0.5 0.5 Fe2
c------------------------------------------------------------
c moment
0.0
c----------------------------------------------------------

Then go to util and arrange the spin of atoms according to your AFM configuration and run the inputsample file. After this you again have to run input file and hence you can achieve the energy and magnetic moment for your desired structure.

Regards,
Qais

[Re:04] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : October 08, 2018 (Mon) 14:40:22

by Hitoshi GOMI

Hello Qais Ali,

My replay to the BBS is not only for you, but also for other beginners.
If you delete my post, my effort becomes a waste of time.
Please summarize the detaild procedure to calculate the anti-ferromagnetic Fe for the other beginners.

> but the total energy values are higher compared to fm and nm bcc-Fe than expected.
Let me know the total energy of fm-bcc, nm-bcc and afm-fcc Fe.

P.S. I have my own works, so that it is not always possible to reply soon.

Hitoshi GOMI

[Re:03] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : September 15, 2018 (Sat) 00:37:48

by Qais Ali

Dear Hitoshi,

Last time you suggested following input for fm-Fe (bcc) calculation.

c-----------------bcc-Fe-fm------------------------------
fsm data/fe_bcc_AFM
c------------------------------------------------------------
c brvtyp a c/a b/a alpha beta gamma
sc 4.95 , , , , , ,
c------------------------------------------------------------
c edelt ewidth reltyp sdftyp magtyp record
0.001 1.0 nrl mjw mag 2nd
c------------------------------------------------------------
c outtyp bzqlty maxitr pmix
update 5 150 0.015
c------------------------------------------------------------
c ntyp
2
c------------------------------------------------------------
c type ncmp rmt field mxl anclr conc
Fe1 1 1 0.0 2
26 100
Fe2 1 1 0.0 2
26 100
c------------------------------------------------------------
c natm
2
c------------------------------------------------------------
c atmicx(in the unit of a) atmtyp
0 0 0 Fe1
0.5 0.5 0.5 Fe2
c------------------------------------------------------------
c moment
0.0
c----------------------------------------------------------

I have opted similar approach for fm-Fe (fcc) and later used it to make afm-Fe (fcc) energy calculations. I can converge the KKR calculations for afm structure of fcc-Fe but the total energy values are higher compared to fm and nm bcc-Fe than expected. Can you please tell that are the energy values biased in this case since I used Fixed Spin Moment? Can we say that total energy values are self-consistent for afm structures of Fe (fcc)? Looking forward to hear from you soon.

Regards,
Qais

[Re:02] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : September 09, 2018 (Sun) 01:17:55

by Qais Ali

Dear Hitoshi,
Yes it was deleted by misktake while I was trying to edit my reply and delete the previous one but the whole post deleted and I could not find an option to recover that, however if you require your last reply to me, I would try to rephrase that here.
Regards,
Qais

[Re:01] Regarding afm fcc-Fe convergance and higher total energy values compared to bcc fm-Fe

Posted on : September 08, 2018 (Sat) 01:48:03

by Hitoshi GOMI

Hello Qais,

I cannot find our previous discussion in the log.
Did you delete it?

Hitoshi GOMI