[Pw_forum] big difference between "total magnetization" and "absolute magnetization" for 4f elements

[琨陶]

Dear everyone,

I want to calculate the magnetic properties of bulk Gd whose magnetic
moment is about 8 Bohr magneto/atom. Usually, in the output file
values of "total magnetization" and "absolute magnetization" should be
nearly the same. However, in my output file, I found a big difference
between them as following:

     total magnetization       =     8.00 Bohr mag/cell
     absolute magnetization    =    15.72 Bohr mag/cell

The good news is that the "absolute magnetization" is close to the
experimental results (7.86 Bohr mag/atom), the bad news is that the
"total magnetization" is wrong. Moreover, when I try to calculate the
magnetic moment on each atom with projwfc.x program, I got about 4.1
Bohr mag/atom.

Could you give me some suggestions? Any advice are appreciated, thanks!

Regards,
Kun Tao


Attached below is the input file:

 &control
    calculation='scf'
    restart_mode='from_scratch',
    prefix='Gd',
    pseudo_dir = './'
    outdir='./',
 /
 &system
    ibrav= 4, celldm(1)= 6.96, celldm(3)= 1.59,
    nat= 2, ntyp=1,
    nspin = 2,
    starting_magnetization(1)=1.0,
    ecutwfc=55.0,
    ecutrho=220.0,
    occupations ='smearing',
    smearing ='gauss',
    degauss = 0.01,
 /
 &electrons
    diagonalization='david',
    mixing_beta = 0.3,
    conv_thr = 1.0d-8,
 /
ATOMIC_SPECIES
 Gd  1.0  Gd.GGA-PBE-paw.UPF
ATOMIC_POSITIONS {crystal}
Gd  0.33333333  0.66666667  0.25
Gd  0.66666667  0.33333333  0.75
K_POINTS {automatic}
4 4 4 0 0 0