[Wien] Plasma frequency

[delamora]

Dear WIEN2k users,

    I want to make some corrections;

    I was not calculating the optic properties correctly, I was using


x optic -up

x optic -dn


for the calculations with spin-orbit coupling

but when I use the correct options;


x optic -c -so -up

x optic -c -so -dn


I get the same 'up' and 'dn' values.

The following is the corrected message;




Dear WIEN2k users,

    I am trying to calculate the plasma frequency for a magnetic system.

    I find that if the calculation is with spin-orbit coupling then the 'up' and 'dn' values are the same, so I tried the CrO2 system;


a=b=4.36A

c=2.897

angles=90

group: 136 (P 42/m n m)


This is a half metal compound, that is, there is a gap in the minority spin (in this case, in other systems the gap is in the mayority spin)


The plasma frequency squared is proportional to the electronic component of the conductivity, so the plasma frequency shoud be cero for the down spin;


runsp -orb

CrO2.outputjointup-       w_p_xx      w_p_zz    [eV]
CrO2.outputjointup-       1.4563      0.9833
CrO2.outputjointdn-       0.0000      0.0000


so far it is fine....


but when the spin-orbit coupling is included then


runsp -orb -so

CrO2.outputjointup-       1.4784      0.9956
CrO2.outputjointdn-       1.4784      0.9956


which is inconsistent with the fact that there is a gap in the 'dn' spin


Here the calculation is not very accurate, that is,

RxK=7 with 100 k-points


But with a more accurate calculation the same inconsistencies are found.


        Saludos


                        Pablo de la Mora

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