[Wien] Antiferromagnetic Calculation With Orbital Potentials

[Pavel Novak]

Dear David,

in the file case.scfdmup (after running the job with s-o) you'll find both 
spin and orbital moment vectors. Be aware that these are calculated only 
for atoms and states selected in case.indmc. Example (one of Fe in Fe3O4):
:ORB008:  ORBITAL MOMENT:  0.10658 -0.00452  0.07161 PROJECTION ON M  
0.10660
:SPI008:  SPIN MOMENT:   3.54034  -0.01460   0.00044 PROJECTION ON M  
3.54036

Regards Pavel


 On Wed, 13 May 2009, David Tompsett 
wrote:

> Thank you Pavel and Stefaan for your help.
> 
> I have one more question about analysing the output from the found 
> ground state.
> 
> I wish to know the effective moment for the ion. How do I combine the 
> orbital moment (as projected along the chosen magnetization direction 
> for SO coupling) and spin moments?
> 
> Thank you,
> David.
> 
> Pavel Novak wrote:
> > Dear David,
> >
> > I believe that two solutions you obtained just reflect the fact that with 
> > very localized 4f states multiple solutions may be obtained, especially 
> > when applying the orbital potentials. Criterion for the ground state is 
> > the lowest total energy. 
> >
> > Regards
> > Pavel 
> >
> > On Tue, 12 May 2009, David Tompsett wrote:
> >
> >   
> >> Dear All,
> >>              I am studying the magnetic ground state of a metallic 
> >> system. The magnetic atoms are Yb, and I am localizing the 4f moment 
> >> using an orbital potential, as well as applying spin-orbit coupling.
> >>
> >> I have a question about the behaviour of the spin moments depending on 
> >> my input to case.inst
> >> Firstly, I set the starting spins such that the 5d electron and 4f hole 
> >> have a net spin and are flipped between the two Yb atoms:
> >> Yb
> >> Xe 4 
> >> 4, 3,3.0  N
> >> 4, 3,3.0  N
> >> 4,-4,4.0  N
> >> 4,-4,3.0  N
> >> 5, 2,1.0  N
> >> 5, 2,0.0  N
> >> 6,-1,1.0  N
> >> 6,-1,1.0  N
> >>
> >> Yb2
> >> Xe 4 
> >> 4, 3,3.0  N
> >> 4, 3,3.0  N
> >> 4,-4,3.0  N
> >> 4,-4,4.0  N
> >> 5, 2,0.0  N
> >> 5, 2,1.0  N
> >> 6,-1,1.0  N
> >> 6,-1,1.0  N
> >> In this case the moments between the two Yb atoms go towards spin 
> >> moments of +2u and -1u during the convergence. Not an antiferromagnetic 
> >> solution.
> >>
> >> Second, I set the 6s spin to 0.5 up and 0.5 down( ie. not net spin) in 
> >> case.inst:
> >> Yb
> >> Xe 4 
> >> 4, 3,3.0  N
> >> 4, 3,3.0  N
> >> 4,-4,4.0  N
> >> 4,-4,3.0  N
> >> 5, 2,0.5  N
> >> 5, 2,0.5  N
> >> 6,-1,1.0  N
> >> 6,-1,1.0  N
> >>
> >> Yb2
> >> Xe 4 
> >> 4, 3,3.0  N
> >> 4, 3,3.0  N
> >> 4,-4,3.0  N
> >> 4,-4,4.0  N
> >> 5, 2,0.5  N
> >> 5, 2,0.5  N
> >> 6,-1,1.0  N
> >> 6,-1,1.0  N
> >> Then, a stable antiferromagnetic solution was found.
> >>
> >> Questions:
> >> 1) Does the different behaviour occur because I am only applying my 
> >> orbital potential to the 4f states and not 5d?
> >>
> >> 2) Is there some other physics to explain this? Is there something that 
> >> I can check to diagnose the behaviour in the first case?
> >>
> >> Thanks,
> >> David.
> >>
> >>
> >>     
> >
> >   
> 
> 

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