[Wien] Optical properties

[Fred Nastos]

On November 25, 2004 04:19 am, Chukwuemeka Okoye wrote:
>
> I am calculating the optical conductivity of bcc iron  and found that the
> absorptive part is not always positive. This means that a plot of
> Re_sigma_xx   Re_sigma_yy  Re_sigma_zz  using  file fe.absorpup has a
> negative part between 2.7eV and about 14.0eV. I think this is strange. This
> is because the mathematical _expression (per spin) for  Re_sigma_xx  etc.
> makes it impossible for it to be negative.

What happens if you do the calculation without spin-orbit.  By "without 
spin-orbit", I do not mean only running only optic/joint part of the 
calculation the without spin-orbit, but running the entire calculation, from 
the start, without spin-orbit.