[Pw_forum] problem with monoclinic cell with ibrav=0

[dev sharma]

hi 2 all,
 I was trying to  draw the monoclinic structure of KY(PO3)4, potassium
yttrium polyphosphate,  with ibrav=0 and i have made it almost. The problem
in my structure is that it is making an extra bond b/w Potassium and
Yttrium  instead of that bond between Potassium and oxygen . All the atoms
are at their positions   but only two bond are swapped.  Means both the
bonds should be in b/w Potassium and oxygen instead of Potassium and
Yttrium.  Please help or give advice. The Details are as follows.
Thanks A lot in advance,



Crystal data

KY(PO3)4
Mr = 443.89
Monoclinic, P21
a = 7.2244 (3) A
b = 8.2825 (3) A
c = 7.854 (4) A
beta = 91.735 (3)
V = 469.7 (2) A3

 My Input file is
&control
/
/
&system
 ibrav=0
   nat=36
 ntyp=4
  ecutwfc=35.0
  ecutrho=200.0,
 occupations = 'fixed'
  /
&electrons
  /
/
ATOMIC_SPECIES
   /
ATOMIC_POSITIONS {crystal}
K    0.270300  0.456600  0.718800
K    0.729700   0.956600   0.281200
Y    0.237040  0.758970  0.242450
Y    0.762960  0.258970  0.757550
P    0.4367  0.3830  0.0947
P    0.5633  0.8830  0.9053
P    0.0994  0.1755  0.0978
P    0.9006  0.6755  0.9022
P    0.9982  0.4085  0.3809
P    0.0018  0.9085  0.6191
P    0.6161  0.5114  0.3992
P    0.3839  0.0114  0.6008
O    0.3212  0.5292  0.0721
O    0.6788  0.0292  0.9279
O    0.5736  0.3558  0.9613
O    0.4264  0.8558  0.0387
O    0.3126  0.2261  0.1093
O    0.6874  0.7261  0.8907
O    0.5360  0.3706  0.2789
O    0.4640  0.8706  0.7211
O    0.0239  0.2062  0.9224
O    0.9761  0.7062  0.0776
O    0.0880  0.0105  0.1732
O    0.9120  0.5105  0.8268
O    0.9924  0.2991  0.2159
O    0.0076  0.7991  0.7841
O    0.1660  0.5100  0.3846
O    0.8340  0.0100  0.6154
O    0.9663  0.3109  0.5348
O    0.0337  0.8109  0.4652
 O    0.8245  0.5225  0.3407
O    0.1755  0.0225  0.6593
O    0.5258  0.6648  0.3514
 O    0.4742  0.1648  0.6486
O    0.6118  0.4535  0.5773
O    0.3882  0.9535  0.4227
 K_POINTS {automatic}
4 5 4 1 1 1
CELL_PARAMETERS
13.65213741740369    0.00000000000000    0.00000000000000
 0.00000000000000   15.65165663025941    0.00000000000000
 -0.44936602772498    0.00000000000000   14.83510473548868


With regards,
Dev Sharma
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