[Wien] density matrix normalization - expectation spin value

[Martin Gmitra]

Hi Robert,
Is there a way to include this somehow?
Thanks,
Martin


On Thu, Feb 4, 2010 at 9:44 AM, Robert Laskowski <
rolask at theochem.tuwien.ac.at> wrote:

> Hi,
> you are missing interstitial contribution.
>
> regards
>
> On Thursday 04 February 2010 09:36:53 Martin Gmitra wrote:
> > Dear Wien2k users,
> >
> > We are interested in calculation of expectation value of spin for a state
> |n,k>,
> > where n is the band index and k is the wave vector. For this purpose we
> have
> > slightly modified lapwdm program. The problem we are encountering is that
> the
> > expectation value of z-component of Pauli matrix (sigma_z) is not equal
> one.
> > Let us assume for simplicity spin-up state |n,k> and no spin-orbit
> coupling.
> > The expectation value for sigma_z we calculate as
> >
> > sum_a ( rho_{n,k,a} sigma_z ) not= 1  (it is smaller then 1, typical
> > range 0.6-0.9)
> >
> > where sum_a is the summation over atoms in unit cell.
> >
> > 1. Why we do not obtain for the state |n,k> expectation value equal one?
> > It is rather obvious that in this example <n,k| sigma_z |n,k> =1.
> >
> > 2. What is the density matrix normalization in this case?
> >
> > rho_{n,k,a} is in this simple example 2x2 matrix having only up-up
> component,
> > which is given as Trace in orbital subspaces (sum for L=0,1,2,3) of given
> state
> > |n,k>.
> >
> > Many thanks in advance,
> > Martin
> >
> > [We are running Wien2k v9.1]
> > _______________________________________________
> > Wien mailing list
> > Wien at zeus.theochem.tuwien.ac.at
> > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> >
> >
>
>
>
> --
> Dr Robert Laskowski
>
> Vienna University of Technology,
> Institute of Materials Chemistry,
> Getreidemarkt 9/165-TC, A-1060 Vienna
>
> tel. +43 1 58801 15675
> Fax  +43 1 58801 15698
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20100204/1a7d6353/attachment.htm>