AW: [Wien] I want to calculate FeNi with lower symmetry

[yasuharu_shiraishi at fujifilm.co.jp]

Dear Torsten Andersen, P. Blaha, and Ciao Gerhard,


Please allow me to explain my purpose in detail.


I want to calculate MAE of ternary ordered alloy for example FeNi,
But I can not converge MAE, and MAE varies with parameter changing for
example R*Kmax.


For example, my calculation of Fe(Ni)Pt2 is as follows.

coordinate of Fe(Ni)Pt2 (two times supercell of FePt)  is

a = 2.72236
b = 5.44472
c = 3.66
Fe(0.0, 0.0, 0.0,), Ni(0.0, 0.5, 0.0), Pt(0.50, 0.25, 0.50), Pt(0.50, 0.75,
0.50)

Parameter of Fe(Ni)Pt2 is

k =1000
Emax =10.0
Gmax =14.0
Rmt(Fe)=Rmt(Ni)=Rmt(Pt)=2.50

if I choose R*Kmax = 8.75 MAE is 0.61mRy.
if I choose R*Kmax = 9.00 MAE is 0.07mRy.

MAE is calculated as follows.
MAE = Total energy of hard axis - Total energy of easy axis.

So MAE is so different with parameter R*Kmax.


But I found a paper as follows.


JAP 93, 6888(2003)
JMMM 264, 7-13(2003)
PRB 67, 214405(2003)
PRB 69, 012404(2004)
PRB 69, 134408(2004)


They calculate MAE using WIEN2k and they converged MAE. And They say they
have to unify the symmetry of
easy axis and hard axis of solid. They calculate YCo5(JMMM 264,
7-13(2003)), which symmetry of easy axis is
P6/mmm, and that of hard axis is Pmmm. And if they do not Pmmm in
calculation of easy axis , 1 - 5meV error
happen which is Wien2k's systematical error.


Is this right ?
So I want to know total energy dependence of symmetry.


Best Regards.
Yasuharu Shiraishi