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["Jess Kondor" <kondor.jess@gmail.com>]

 Dear all,

  I tried to use abinit geometry optimizer to build whole structure using crystallographic data. I have:
   BiMnO3,  C2 group (#5) , volume = 491.7 Ang^3
a = 9.854 , b =   5.606 , c =  9.532 (Ang) , alpha = gamma=
90.0 ; beta=110.60
11
    Mn1 Mn 4c  0.254 0.062 0.757 
    Bi2   Bi  4c  0.359 0.1 0.115 
    Mn3 Mn 2a  0.0 0.0 0.0 
    O4   O  4c   0.144 0.257 0.106 
    O5   O  4c   0.346 0.363 0.415 
    O6   O  4c  
0.365 0.276 0.915 
    O7   O  4c  0.1 0.015 0.838 
    O8   O  4c  0.4 0.169 0.672 
   Mn9 Mn 2b  0.5 0.096 0.5 
   Bi10 Bi  4c  0.135 0.037 0.372 
   O11 O  4c  0.149 0.405 0.63 

the corresponding part of the input file is :

spgroup 5
brvltt -1
acell  9.854   5.606   9.532  Angstr
angdeg 90.0 110.60 90.0

ntypat 3
natom  20
natrd 11
typat  2*1 3*2 6*3
xred
       0.359 0.1 0.115 
      0.135 0.037 0.372
 
      0.0 0.0 0.0 
      0.254 0.062 0.757 
      0.5 0.096 0.5 
      0.144 0.257 0.106 
      0.346 0.363 0.415 
      0.365 0.276 0.915 
      0.1 0.015 0.838 
      0.4 0.169 0.672 
      0.149 0.405 0.63 


I see in the output file:
 Symmetries : space group C2 (#  5); Bravais mC (1-face-center monocl.)

but the unit cell volume is almost twice smaller and the angles are strange:

 Real(R)+Recip(G) space primitive vectors, cartesian coordinates (Bohr,Bohr^-1):
 R(1)=  9.0064347  5.2959575  0.0000000  G(1)=  0.0555159  0.0944116  0.0208670
 R(2)= -9.0064347  5.2959575  0.0000000  G(2)= -0.0555159  0.0944116 -0.0208670
 R(3)= -6.5484460  0.0000000 17.4218583  G(3)=  0.0000000
  0.0000000  0.0573992
 Unit cell volume ucvol=  1.6619650E+03 bohr^3
 Angles (23,13,12)=  7.23445051E+01  1.07655495E+02  1.19087300E+02 degrees

V = ~1661 bohr^3  = ~ 246 Ang^3

Did I miss something?

  Thanks,
     jess