Hello, I have read the manual for MAGMOM-tag. I have 4 atoms; C H S and Ni. I assume that this tag requests the initial magnetic moment for each atom. In this case I put MAGMOM = 0 0 0 28*0.6*1.3 (1.3 for scaling of expt. val. Ni mag.mom.). So, Is this correct? When trying to run I receive error reading 'MAGMOM' from INCAR. Error code was IERR=0 ... . Found N= 4 data.
Question: What is the proper format of this tag?
A clearer explanation in VASP UG may be needed. (?)
Thank You
W
MAGMOM-tag
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fabella
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MAGMOM-tag
Last edited by fabella on Tue Feb 21, 2006 4:00 am, edited 1 time in total.
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MAGMOM-tag
28*0.6*1.3 is not a valid format to read a magnetic moment.
for 3 non-magnetic and 28 magnetic atoms,
MAGMOM can be given like
3*0 28*0.9
0 0 0 28*0.9
or you can give each moment explicitely
Please mind that the MAGMOM specified in INCAR is just a starting guess, the actual self-consistent magnetic moments will be calculated as the electronic structure converges.
for 3 non-magnetic and 28 magnetic atoms,
MAGMOM can be given like
3*0 28*0.9
0 0 0 28*0.9
or you can give each moment explicitely
Please mind that the MAGMOM specified in INCAR is just a starting guess, the actual self-consistent magnetic moments will be calculated as the electronic structure converges.
Last edited by admin on Tue Feb 21, 2006 10:45 am, edited 1 time in total.
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fabella
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MAGMOM-tag
TY for the info.
Now, it seems I have a problem with convergence (Continuation job ISTART=1, ICHARG=1, i have WAVECAR and CHGCAR. I can guess that the problem started when adding the ISPIN=2 (spin-polarization). I ran two calculations one with MAGMOM set appropriate, the other without MAGMOM.
-The first case does not even finish the first sc loop (-c gives 35).
-The second case gets through the first sc loop then mid-way through the second 'stops' without notification ... just "hangs" there.
One thing in common, they both are sitting 'about' the same energy (within 1eV of each other). "They are screaming to converge"
How do I successfully troubleshoot "solve" this issue ... I was thinking of a couple things. 1) Maybe I should rerun previous relaxation of structure with strict force criteria ( <0.05 eV/A instead of <0.08 eV/A ), then run with spin polarization w/o relaxation. 2) I think my initial structure is close to equilibrium so I use IBRION=1, maybe I should use IBRION=2 (much slower) to relax and find equilibrium positions ... then turn on spin-polarization. (?) I think this with some uncertainty and time constraints. Could you be of any assistance here, maybe this situation is quite common if the structure is not 'well' relaxed before switching on ISPIN=2.
THANKX
W
Now, it seems I have a problem with convergence (Continuation job ISTART=1, ICHARG=1, i have WAVECAR and CHGCAR. I can guess that the problem started when adding the ISPIN=2 (spin-polarization). I ran two calculations one with MAGMOM set appropriate, the other without MAGMOM.
-The first case does not even finish the first sc loop (-c gives 35).
-The second case gets through the first sc loop then mid-way through the second 'stops' without notification ... just "hangs" there.
One thing in common, they both are sitting 'about' the same energy (within 1eV of each other). "They are screaming to converge"
How do I successfully troubleshoot "solve" this issue ... I was thinking of a couple things. 1) Maybe I should rerun previous relaxation of structure with strict force criteria ( <0.05 eV/A instead of <0.08 eV/A ), then run with spin polarization w/o relaxation. 2) I think my initial structure is close to equilibrium so I use IBRION=1, maybe I should use IBRION=2 (much slower) to relax and find equilibrium positions ... then turn on spin-polarization. (?) I think this with some uncertainty and time constraints. Could you be of any assistance here, maybe this situation is quite common if the structure is not 'well' relaxed before switching on ISPIN=2.
THANKX
W
Last edited by fabella on Wed Feb 22, 2006 3:29 am, edited 1 time in total.