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Can Abinit investigate the valence state of the complex oxides?

Dear everyone:
        I want to use Abinit code to investigate a question of valence with 
the real physical background. It is well known that the valence states of La, 
Mn are 3+ in LaMnO3. When a Ca cation is substituted for La, Ca is 2+ and a 
Mn3+ ion near the Ca ion changes into Mn4+. However, after imaging the charge 
density given by Abinit, I find that there is no significant difference 
between the charge density of Mn ions near the Ca ions and that of the Mn 
ions near La ions.
        The input file is enclosed as below and Troullier-Martins 
pseudopotentials are used. The lattice parameters and the coordinates of ions 
came from atomic simulation method, which are in agreement with some 
experimental data approximately. Then, my questions are: i) Can Abinit code 
investigate such complex compound as manganite? ii) Can Abinit code 
investigate the valence state of elements in oxides? iii) Is there something 
wrong in my input file? or I used the wrong pseudopotentials? Any help or 
comment is welcomed.
        Thank you very much!
                                  F. L. Tang


The input file:
# Description
# To compute the charge density of Ca doped LaMnO3

 #Definition of the unit cell
 acell  30.54614509 7.117517053 10.19366793
 chkprim 0
 rprim  1.0  0.0  0.0
        0.0  1.0  0.0
        0.0  0.0  1.0

 #Definition of the atom types
 ntypat 4
 znucl  20 57 25 8 

 #Definition of the atoms
 natom 30
 typat 4*1 2*2 6*3 18*4
 xred

0.315292496 0.499992718 -0.008456786
0.640264554 0.499997562 -0.012080163
0.480905516 0.499998037 0.466623656
0.796570507 0.499998892 0.483776997
0.131429075 0.499997087 0.47381952
-0.029729909 0.499997942 -0.037183826
0.162524214 -0.002453255 -0.025542832
0.642978223 -0.001745869 0.478231266
0.802045238 -0.000896629 -0.017568346
0.324384057 0.000890791 0.482435297
0.483450688 0.001737762 -0.021767894
-0.036094665 0.002445169 0.474456237
0.252337515 -0.082451313 0.206027825
0.077293439 -0.052378973 0.229870323
0.739903207 -0.052276898 0.280369744
0.417357252 -0.04684778 0.268495351
0.903759099 -0.045289295 0.162363442
0.579054307 -0.040021775 0.18279104
0.547374486 0.040014125 0.682789217
0.222669413 0.045285143 0.662367223
0.7090716 0.046837352 0.768492609
0.386525409 0.052272394 0.78037337
0.049136428 0.052371391 0.729869726
0.874092104 0.082447617 0.706024686
0.489799807 0.499994966 0.027902736
-0.022933813 0.499995346 0.404421367
0.332761907 0.499995979 0.42487798
0.169923818 0.499996486 0.027521008
0.645686522 0.499997056 0.432654719
0.797710508 0.499998449 0.042815201

 #Definition of the planewave basis set
 ecut 75

 #Definition of the k-point grid
 nkpt 3 
 nband 120

 #Definition of the SCF procedure
 nstep 50
 toldfe 1.0d-10
 #Output
 occopt 3 

 tsmear 0.05
 prtden 1