[Wien] EFGs in the spin-polarized calculations

[Stefaan Cottenier]

> I am performing the electric field gradients (EFGs) calculation
> considering the spin-polarization. I found that EFGs could only be
> calculated for spin-up and spin-down electrons separately. As far as I
> know, the EFGs are only determined by coulomb potential or charge
> distribution, and not related to spin channels. Thus, it seem that I
> need to sum the EFGs for both spins, to obtain real EFGs. Is this
> correct?

You are probably looking at :VZZxxx, which is the spin-resolved EFG  
within the muffin-tin sphere. The number that is relevant for  
experiments is :EFGxxx, which is :VZZxxx-up + :VZZxxx-dn +  
interstitial contribution.

Projecting the total EFG onto the different spin channels can be  
useful to find out which kind of electrons are contributing to it, and  
why. See for instance PRB 74 014409, Tabs. 4 and 8.

Stefaan