[Wien] Fwd: problem in hyperfine field of Gd

[susanta mohanta]

Dear  Prof. Blaha andWien Users,
We  are working in some rare-earth systems. We have made calculations
with R_mt=2.9, RKmax=9.5 and k-mesh=20x20x11. For Pure Gd we are getting
most of
the physical properties like unitcell parameters (optimized with GGA and
GGA+U+SO) consistent with some of the recent calculations using wien2K as
well as experiment. Howerver, we find that the hyperfine field is positive;
+270KG
with core HFF = -2893kG and HFF_val= +3163kG (in case of GGA) and +223kG
with
HFF_core= -2931kG and HFF_val= +3154kG(incase of GGA+U with U_eff = 0.6).
The experimental value for HFF of Gd in Gd is reported to be -350kG. The
negative sign is what one would expect for the spin only moment of Gd. We
made
calculations with U_eff ranging from 0.4 to 0.7, Rmt changing from 2.6 to
3.0,
RKmax from 8 to 10 but the sign of HFF always comes to be positive.
While, magnitude may be acceptable, can some one clarify why the sign comes
out opposite. Am I making some trivial mistake.

we are working with wien2k9.1 version. We fell valence contribution is over
estimated.
Any suggestion in this regard ?

with sincere regards
susanta
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20091113/059bca30/attachment.htm>