[xcrysden] PWscf structure in xcrysden problem

[W. YU]

Dear XcrysDen uses, =0A=0AI have been testing again an again for it to show=
 my PWscf input files. I met several problems=0Aand I really appreciate if =
someone could help me out.=0A=0A1. I tried a very simple NaCl structure inp=
ut . But when I changed the parameter=0A   Celldm(1) value, some times, it =
jush shows parts of the atoms and sometimes =0A   it works  well. I am real=
ly confused about this "strange?" behaviour. The input which =0A   is not s=
hown properly is  as follows: =0A   ( If I change the celldm(1) to other va=
lues such as 6.92, it does work.)=0A=0A=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=0A &control=0A   calculation =
=3D 'scf',=0A   restart_mode =3D 'from_scratch',=0A   outdir =3D '/root/pws=
cf_workspace/tmp/',=0A   pseudo_dir =3D '/root/pwscf/pseudo/',=0A   tstress=
 =3D .true.=0A /=0A &system    =0A    ibrav =3D 2, celldm(1) =3D6.93,=0A   =
 nat=3D 2, ntyp=3D 2,ecutwfc =3D 25.0,ecutrho =3D 200.0,=0A/=0A&electron=0A=
   conv_thr =3D  1.0d-8=0A    mixing_beta =3D 0.7=0A/=0AATOMIC_SPECIES=0A N=
a 6.941  Li_VDB_LDA_SEMI.UPF =0A Cl  1.008  H.pz-van_ak.UPF =0AATOMIC_POSIT=
IONS  =0A Na 0.00 0.00 0.00 =0A Cl 0.50 0.50 0.50 =0AK_POINTS automatic =0A=
  8 8 8  1 1 1 =0A =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=0A 2. I =
found if the input atomic positions are not in the same PRIMITIVE =0A    un=
it cell, it cannot be shown well. Is this true? If so, I have to give=0A   =
 all the atomic coordinates in the same PRIMITIVE unit cell. But ]=0A    th=
is is sometimes not so convenient say if we have a BCC structure =0A    of =
several atoms. Even a simple NaCl structure will not work the way=0A    it =
is supposed to if the two atomic coordinates (for Na and Cl) are =0A    giv=
en as follow:  =0A=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=0AATOMIC_POSITIONS  =0A Na 0.00 0.00 0.00 =0A Cl 0=
.50 0.00 0.00 =0A=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=0A    And the following is a complet input of anot=
her BCO structure input =0A    for Li2CuO2 which doesn't look the way it sh=
ould be:=0A=0A=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=0A &control=0A   title =3D Li2CuO2 ,=0A   calculat=
ion =3D 'scf' ,=0A   restart_mode =3D 'from_scratch' ,=0A   outdir =3D '/ro=
ot/pwscf_workspace/tmp/' ,=0A   pseudo_dir =3D '/root/pwscf/pseudo/' ,=0A  =
 prefix =3D Li2CuO2 ,=0A   tstress =3D .true. ,=0A   tprnfor =3D .true. ,=
=0A /=0A &system=0A   ibrav =3D 11,=0A   celldm(1) =3D 6.9051,=0A   celldm(=
2) =3D 0.78188,=0A   celldm(3) =3D 2.6634,=0A   nat =3D 5,=0A   ntyp =3D 3,=
=0A   ecutwfc =3D 25 ,=0A   ecutrho =3D 200 ,=0A /=0A &electron=0A   mixing=
_beta =3D 0.2 ,=0A   diagonalization =3D 'cg' ,=0A /=0AATOMIC_SPECIES=0A   =
Li    6.94100  Li.pz-s-van_ak.UPF =0A   Cu   63.55000  Cu.pz-n-van_ak.UPF =
=0A    O   16.00000  O.pz-van_ak.UPF =0AATOMIC_POSITIONS crystal =0A   Li  =
    0.500000000    0.000000000    0.289200000    0  0  0 =0A   Li      0.50=
0000000    0.000000000    0.710800000    0  0  0 =0A   Cu      0.000000000 =
   0.500000000    0.500000000    0  0  0 =0A    O      0.000000000    0.000=
000000    0.357600000    0  0  0 =0A    O      0.000000000    0.000000000  =
  0.642400000    0  0  0 =0AK_POINTS automatic =0A  4 4 2   1 1 1 =0A=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=0ASorry for=
 this lengthy email and thanks a lot if anybody knows the =0Aanswer.=0A=0AB=
est,=0A=0AWen Yu=0A=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=0A=
=0ADr. Wen Yu=0A=0APhysics Department=0AUniversity of Science and Technolog=
y of Beijing,=0Awenyu@sas.ustb.edu.cn=0A=0A=0A =0A_________________________=
___________________________________________________________=0AAny questions=
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