[Wien] calculation of electron-phonon coupling constant

[Peter Blaha]

Modify atpar.f and put a loop over energies around it (check Hartree and 
Ry!). Then use directly the parameters printed as function of E.
(I think u_l is r.P_l !)

> I´m trying to evaluate the following Multiple Scattering formula which yield
> the
> tan of the phase shifts d at the energy E and raddi R.
> 
> tan d =(RK j'_l(KR) -b_l j_l(KR) ) / (RK n'_l(KR) -b_l n_l(KR) )
> 
> where b_l are the logarithmic derivatives of the radial function u_l at R
> and E, K is
> sqrt(E) and j, j' n, n' are the spherical bessel the r-derivative of the
> spherical bessel
> and the corresponding neumann functions.
> 
> Everything is tested and works pretty fine.
> 
> I tried to evaluate the  b_l (logarithmic derivatives of u_l) by means of
> the "Potential Parameters"
> obtained in lapw1 (sub atpar) employing the linear definition of u_l
> 
> u_l(r,E) = u_l(r,E_l) +(E-E_l) du_l/dE
> 
> Now, trying to reproduce the well known results for Nb, I obtained
> significant differences in the phase-shifts.
> 
> I feel that I´m dropping out something in the u_l construction.
> In the formal theory, u_l involves two constants A_l and B_l. In atpar they
> are already considered?
> 
> Any help is acknowledged.
> 
> Emilio Orgaz
> 
> On 6/29/06, Peter Blaha <pblaha at theochem.tuwien.ac.at> wrote:
> > 
> > In case.output1 you find the relevant "potential parameters", i.e.
> > u_l(RMT), du/dr; du/de,...
> > 
> > Otherwise, the routine   atpar.f   calculates the radial wavefunctions.
> > 
> > Regards
> > 
> > > I´m interested on the electron-phonon coupling constant calculated
> > > a la Gaspari-Gyorffy. For this, I need the phase shifts for different
> > > chanels.
> > >
> > > I know that those phase shifts can be obtained from the log-derivitives
> > of
> > > the radial function
> > > u_l(r) at the MT radii.
> > >
> > > I would like to know how to extract  u_l(r) and the corresponding
> > log-der
> > > from WIEN2K code.
> > >
> > > thank you in advance for your help
> > >
> > > Emilio Orgaz
> > >
> > > On 10/13/05, Ashok Kumar Verma <hpps at magnum.barc.ernet.in> wrote:
> > > >
> > > > Dear WIEN users,
> > > >              Is there anyone who can tell me how  to calculate the
> > > > electron-phonon coupling constant using WIEN. I saw one paper by P.
> > Blaha
> > > > (PRB 62, 6774) where this has been done within the rigid muffin-tin
> > > > approximation. But i dod not knos how to do it.
> > > > thanking in advance
> > > >
> > > >
> > > >
> > > > _______________________________________________
> > > > Wien mailing list
> > > > Wien at zeus.theochem.tuwien.ac.at
> > > > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> > > >
> > >
> > >
> > >
> > > --
> > > Dr. Emilio Orgaz
> > > Departamento de Física y Química Teórica
> > > Facultad de Química, UNAM
> > > Emilio.Orgaz at gmail.com
> > > Tel.  5622-3776
> > > Fax. 5622-3521
> > >
> > 
> > 
> >                                       P.Blaha
> > --------------------------------------------------------------------------
> > Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
> > Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
> > Email: blaha at theochem.tuwien.ac.at    WWW:
> > http://info.tuwien.ac.at/theochem/
> > --------------------------------------------------------------------------
> > _______________________________________________
> > Wien mailing list
> > Wien at zeus.theochem.tuwien.ac.at
> > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> > 
> 
> 
> 
> -- 
> Dr. Emilio Orgaz
> Departamento de Física y Química Teórica
> Facultad de Química, UNAM
> Emilio.Orgaz at gmail.com
> Tel.  5622-3776
> Fax. 5622-3521
> 


                                      P.Blaha
--------------------------------------------------------------------------
Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
--------------------------------------------------------------------------