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[v.sokhan@imperial.ac.uk]

Hi Abinitians,

For my research I needed to calculate the bulk structure of alpha-Mn (A12). 
It is perhaps one of the less trivial simple elemental solids and according 
to crystal lattice structures database 
(http://cst-www.nrl.navy.mil/lattice/index.html) its BCC primitive cell 
includes 29 atoms (58 in total for the cubic cell). I prepared an input file 
and when I run it without BCC rprim array (commented out), abinit recognises 
the structure as #215 (P-43m), but with rprim included, abinit fails to 
recognise the structure at all ("the space group has not been recognized") (I 
expected #217, I-43m in this case). I have carefully checked the lattice 
vectors and am pretty sure that they are correct. To pin down the problem, I 
found a more simple substance with the same symmetry group, SiF4, and run a 
job on it: an input file is attached below for your inspection. The problem 
remains, i.e. abinit defines the symmetry as P-43m w/o rprim, and "..not 
recognized" with rprim. Apparently, I am doing something wrong, but couldn't 
figure it out and would appreciate very much any thoughts on the subject. 
Thank you for your attention and apologies for the lengthy posting: haven't 
got time to make it shorter.

Vlad

#-- begin input file -------------------------------------------------
#-- Test of symmerizer: SiF4 structure

# Unit cell parameters
acell   3*10.244d0
rprim  -0.5  0.5  0.5
        0.5 -0.5  0.5
        0.5  0.5 -0.5

ntypat  2
znucl  14.0  9.0
natom   5
typat   1 4*2

optcell 1
ionmov  3
kptopt  1
ecutsm  0.1d0
dilatmx 1.05d0

xred    3*0.0d0
        3*0.165
        0.165 -0.165 -0.165
       -0.165  0.165 -0.165
       -0.165 -0.165  0.165

nstep  30
ntime  20
toldfe  1.0d-8
ecut    2.0d1

ngkpt  4 4 4

diemac  1.0
diemix  0.5
#-- end input file -------------------------------------------------