[Wien] runafm_lapw and runsp_lapw

[Nandan Tandon]

Thank you Prof. Blaha.
I have followed the instructions in the UG for the AFM calculations. Also, 
this behaviour is only observed in the cases where the AF atoms are not 
alike. For cases where the AF atoms are identical the calculations do work 
as expected i.e. the (energy_AF - energy_FM) is about 0.15 Ry or smaller.

Thank you again, now i know which energies to trust.

Nandan.

On Wed, 5 Apr 2006, Peter Blaha wrote:

> You are doing something wrong in the AFM calculation.
>
> The difference between AF and FM is in most cases very small, in the order of a
> few mRy, but never ever 10Ry.
>
> Trust the runsp results.
>
>>
>> I am doing calculations for determining whether the FM or AFM configuration is
>> more favourable using the runsp_lapw and runafm_lapw scripts respectively by
>> changing the inst file for AFM config.
>>
>> In some of the cases the AFM energy is lower compared to the FM configuration
>> by 10Ryd. As suggested in the UG i usually execute the runsp_lapw after
>> runafm_lapw to check whether the total energy changes. The total energy
>> increases and if runsp_lapw is continued the total energy comes very close to
>> the FM configuration energy.
>>
>> Now i dont understand which result to trust.
>>
>> I should mention that the two magnetic atoms in the system are different and i
>> have allowed convergence upto 0.00001. When the magnetic atoms are identical,
>> i dont get this problem.
>>
>> Has anyone faced this problem, and how was it solved.
>>
>> Nandan.
>>
>> --
>> ******************************************************************************
>> Nandan Tandon
>> Research Student
>> Department of Physics,
>> University of Pune     Mob:(0)9423018605
>> Pune-411007                             Tel.(O)+91-20-25692678 ext 426
>> MAHARASHTRA, INDIA.                     Fax.(O)+91-20-25691684
>> ******************************************************************************
>>
>> _______________________________________________
>> Wien mailing list
>> Wien at zeus.theochem.tuwien.ac.at
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>>
>
>
>                                      P.Blaha
> --------------------------------------------------------------------------
> Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
> Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
> Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
> --------------------------------------------------------------------------
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-- 
******************************************************************************
Nandan Tandon
Research Student
Department of Physics,
University of Pune			Mob:(0)9423018605
Pune-411007                             Tel.(O)+91-20-25692678 ext 426
MAHARASHTRA, INDIA.                     Fax.(O)+91-20-25691684
******************************************************************************