How to calculate AFM state (not DLM states)

Posted on : December 28, 2020 (Mon) 10:09:19

by kristofer

Dear AkaiKKR Administrator,
I have difficulties to calculate an AFM state, i calculated the energy of the antiferromagnetic state and found that the result is similar with LMD energy.

my inputsample_dlm
../fileFM 1 2 3 4
../fileDLM 1 2 -2 3 4
my inputsample_AFM
../fileFM 1 2 3 4
../fileAFM 1 -1 2 -2 3 -3 4 -4

the composite in file.inp

#---------------------------------- 0 ----------------------------------
# now # can be used as comment lines as well
#--------------------------------------------
go data/fileFM fcc 8.534002564422,1.0,1.0,90.0,90.0,90.0,
0.001 1.9 sra pbe mag 2nd
update 5 500 0.010
3
#--------------------------------------------
# name of type, number of components, rtr,
# field, lmax, atomic number, concentration
#--------------------------------------------
Ti 2 0 0.0 2 22 90
23 10
O 1 0 0.0 2 8 100
Vc 1 0 0.0 2 0 100
4
0.00000000 0.00000000 0.00000000 Ti
0.25000000 0.25000000 0.25000000 O
0.75000000 0.75000000 0.75000000 O
0.50000000 0.50000000 0.50000000 Vc



A. Kristofer

[Re:02] How to calculate AFM state (not DLM states)

Posted on : December 29, 2020 (Tue) 23:11:25

by kristofer

dear administrator

I would like to thank you for your favorable response.
I changed the structure to the Tetragonal and tried again.
I have obtained good results thanks to your advice.
I have a request from you if possible, to give me references related to AF type for other structures i.e. zinc blende structure. I searched for this type and found nothing.

A. kristofer

[Re:01] How to calculate AFM state (not DLM states)

Posted on : December 28, 2020 (Mon) 14:06:50

by root

It seems that you are trying to calculate AF bcc TiO2 (and not an lmd state). I am wondering if such TiO2 actually exists. Anyway, in this case you have to construct the crystal structure so as to realize AF magnetic structure. For example, if you are considering G-type AF (i.e. Q=(1,1,1)), the best way is take the rhombohedral Bravia lattice (specify try or rho instead of fcc). In this case up/down lair stack along (111) direction (in the cubic frame). Or, if it is A-type or C-type, simple tetragonal lattice system (not fcc) is adequate. In those cases, the system can have tow magnetic sub lattices that can represent AF magnetic structures.

KKR-administrator