[Pw_forum] question about constrained magnetization

[Cyrille Barreteau]

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
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Batiment 462       |
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================================================================== 

===============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

==================================