[Pw_forum] question about constrained magnetization
Cyrille Barreteau
cyrille.barreteau at cea.fr
Wed Dec 2 14:19:44 CET 2009
Dear all,
I want to perform a calculation using the penalization technique.
In an unconstrained scf calculation the input_magnetization(i) (i=1,ntyp)
variable contains the m/n initial value of atom of type i, and this
quantity should
obviously belong to [-1,1] interval.
To perform a constrained magnetization of "atomic type" I have to
set the variable constrained_magnetization='atomic' and the magnetization
will be the one given by input_magnetization(i).
Therefore now input_magnetization(i) is no longer m/n but m only.
However it seems that the range of input_magnetization has not been
modified and is still within [-1,1] interval.
If ever I set input_magnetization(i)>1 then the code automatically
replace it by 1 and I cannot explore values larger than 1.
Is there a way to circumvent this problem?
For clarity I have added below a simple example illustrating my problem.
thanks in advance..
cyrille
--
==================================================================
Cyrille Barreteau | phone : +33 (0)1 69 08 29 51
CEA Saclay | fax : +33 (0)1 69 08 84 46
DSM/IRAMIS/SPCSI | email cyrille.barreteau at cea.fr
Batiment 462 |
91191 Gif sur Yvette Cedex FRANCE
~~~~~~~~~~~~~~~~~~~~~~~~
http://iramis.cea.fr/Images/Pisp/cbarreteau/cbarreteau_fr.html
==================================================================
===============INPUT=============
&control
calculation = 'scf'
restart_mode='from_scratch',
prefix='chromium',
tstress = .true.
tprnfor = .true.
pseudo_dir = '/home/phabibi/SOFTWARE/espresso-4.1.1/pseudo/',
outdir='/home/phabibi/tmp/'
/
&system
ibrav= 1, celldm(1) =5.44, nat= 2, ntyp= 2, nspin = 2,
constrained_magnetization=atomic, lambda=5.0,
starting_magnetization(1)=1.6,starting_magnetization(2)=-1.6,
ecutwfc =40,ecutrho = 300,
occupations='smearing',smearing='mp',degauss=0.005
/
&electrons
diagonalization='cg'
mixing_mode = 'plain'
mixing_beta = 0.7
conv_thr = 1.0d-8
/
ATOMIC_SPECIES
Cr1 51.9961 Cr-gpbe-n-campos.uspp.UPF
Cr2 51.9961 Cr-gpbe-n-campos.uspp.UPF
ATOMIC_POSITIONS
Cr1 0.00 0.00 0.00
Cr2 0.50 0.50 0.50
K_POINTS automatic
10 10 10 0 0 0
==================================
===============OUTPUT=============
Program PWSCF v.4.1 starts ...
Today is 2Dec2009 at 14:38:45
For Norm-Conserving or Ultrasoft (Vanderbilt) Pseudopotentials or PAW
Current dimensions of program pwscf are:
Max number of different atomic species (ntypx) = 10
Max number of k-points (npk) = 40000
Max angular momentum in pseudopotentials (lmaxx) = 3
Waiting for input...
Generating pointlists ...
new r_m : 0.3572
bravais-lattice index = 1
lattice parameter (a_0) = 5.4400 a.u.
unit-cell volume = 160.9892 (a.u.)3
number of atoms/cell = 2
number of atomic types = 2
number of electrons = 12.00
number of Kohn-Sham states= 10
kinetic-energy cutoff = 40.0000 Ry
charge density cutoff = 300.0000 Ry
convergence threshold = 1.0E-08
mixing beta = 0.7000
number of iterations used = 8 plain mixing
Exchange-correlation = SLA PW PBE PBE (1434)
celldm(1)= 5.440000 celldm(2)= 0.000000 celldm(3)= 0.000000
celldm(4)= 0.000000 celldm(5)= 0.000000 celldm(6)= 0.000000
crystal axes: (cart. coord. in units of a_0)
a(1) = ( 1.000000 0.000000 0.000000 )
a(2) = ( 0.000000 1.000000 0.000000 )
a(3) = ( 0.000000 0.000000 1.000000 )
reciprocal axes: (cart. coord. in units 2 pi/a_0)
b(1) = ( 1.000000 0.000000 0.000000 )
b(2) = ( 0.000000 1.000000 0.000000 )
b(3) = ( 0.000000 0.000000 1.000000 )
PseudoPot. # 1 for Cr read from file Cr-gpbe-n-campos.uspp.UPF
Pseudo is Ultrasoft + core correction, Zval = 6.0
Generated by new atomic code, or converted to UPF format
Using radial grid of 857 points, 3 beta functions with:
l(1) = 0
l(2) = 1
l(3) = 2
Q(r) pseudized with 6 coefficients, rinner = 1.300 1.300 1.300
1.300 1.300
PseudoPot. # 2 for Cr read from file Cr-gpbe-n-campos.uspp.UPF
Pseudo is Ultrasoft + core correction, Zval = 6.0
Generated by new atomic code, or converted to UPF format
Using radial grid of 857 points, 3 beta functions with:
l(1) = 0
l(2) = 1
l(3) = 2
Q(r) pseudized with 6 coefficients, rinner = 1.300 1.300 1.300
1.300 1.300
atomic species valence mass pseudopotential
Cr1 6.00 51.99610 Cr( 1.00)
Cr2 6.00 51.99610 Cr( 1.00)
Starting magnetic structure
atomic species magnetization
Cr1 1.000
Cr2 -1.000
==================================
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