[Wien] Force minimization, net magnetic moment

[Ali Baghizhadeh]

Dear Prof. Blaha

For oxygen ions there are some moments that I do not understand it. Without force minimization, net moments is zero.

MMT: 0.94

:MMI001: MAGNETIC MOMENT IN SPHERE   1    =    0.00070  (Lu1)

:MMI002: MAGNETIC MOMENT IN SPHERE   2    =    0.00769 (Sc1)

:MMI003: MAGNETIC MOMENT IN SPHERE   3    =    0.00593 (Sc2)

:MMI004: MAGNETIC MOMENT IN SPHERE   4    =   -0.00353 (Lu2)

:MMI005: MAGNETIC MOMENT IN SPHERE   5    =    3.78782 (Fe1)

:MMI006: MAGNETIC MOMENT IN SPHERE   6    =   -0.05026 (O)

:MMI007: MAGNETIC MOMENT IN SPHERE   7    =    0.08167(O)

:MMI008: MAGNETIC MOMENT IN SPHERE   8    =   -0.12328(O)

:MMI009: MAGNETIC MOMENT IN SPHERE   9    =    0.14614(O)

:MMI010: MAGNETIC MOMENT IN SPHERE  10    =   -0.31444(O)

:MMI011: MAGNETIC MOMENT IN SPHERE  11    =    0.34985(O)

:MMI012: MAGNETIC MOMENT IN SPHERE  12    =   -0.33067(O)

:MMI013: MAGNETIC MOMENT IN SPHERE  13    =    0.36226(O)

:MMI014: MAGNETIC MOMENT IN SPHERE  14    =   -3.59472  (Fe2)

Best regards
Ali


-----Original Message-----
From: Wien [mailto:wien-bounces at zeus.theochem.tuwien.ac.at] On Behalf Of Peter Blaha
Sent: Friday, 13 March 2020 16:21
To: wien at zeus.theochem.tuwien.ac.at
Subject: Re: [Wien] Force minimization, net magnetic moment



I don't understand:

  MMT= 0.00184, MMI: Fe1=3.63779, Fe2=-0.35915



How can a moment of +3.6 and -0.35 cancel to almost zero moment in the cell ??

There must be some other atoms carrying a sizable moment.



or  MMT= 0.95, MMI: Fe1=3.78782, Fe2=-3.59472 these 2 Fe moments nearly cancel, bu you have a large MMT  ???



Check the other moments. And if you stated those atoms with FM moments (Lu, Sc, O), redo the calculations with either zero or AFM moments for these atoms.



On 3/13/20 3:59 PM, Ali Baghizhadeh wrote:

> Dear WIEN2k users

>

> I am running force minimization on my structure, h-(Lu0.5Sc0.5)FeO3,

> with Fe spins up (Fe1) and down (Fe2) in two alternative planes (so

> net zero magnetic moment in unit cell), WIEN2k_19.1, RKMAx:7.

>

> However whatever criteria I am using, the net magnetic moment goes to

> some values around 1 once I run force minimization. In normal scf run,

> only if the charge criteria is low like 0.001 or no charge

> convergence, I may face net magnetic moment.

>

> A typical procedure of force minimization is like this:

>

> 1-Coverge scf: runsp_lapw -p -fc 1 -ec 0.00001 -cc 0.00001 (result:

> MMT= 0.00184, MMI: Fe1=3.63779, Fe2=-0.35915).

>

> 2-min -I -j "runsp_lapw -p -I -i 120 -cc 0.00001 -fc 2" (also tried

> fc=5 and 1), (result: MMT= 0.95, MMI: Fe1=3.78782, Fe2=-3.59472)

>

> I would like to know weather I am running wrong commands or I am

> missing something else, as Lawrence Mark in his text

> "Optimization-Notes", mentioned that for spin polarized cases, force

> minimization may need more care.

>

> * I did not see any warning in scf files.

>

> Best regards and thank you.

>

> Ali

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20200313/e026eed0/attachment.html>