Problem with CIF import of hexagonal structures
Michael Fischer
domm... at gmx.de
Fri Feb 17 14:21:08 UTC 2012
Hello everyone,
I am a newbie to CP2K trying to perform standard DFT calculations on a
variety of different structures. To do so, I usually use the import of
CIF files, e.g.:
&TOPOLOGY
CONNECTIVITY OFF
COORD_FILE_FORMAT CIF
COORD_FILE_NAME MWW.cif
&END TOPOLOGY
This worked fine for several structures for orthogonal cells. However,
when I use a CIF file of a hexagonal cell that has atoms located on
one of the cell planes (i.e. one of x,y,y = 0), the calculation
crashes. After some time, I found out that this is caused by the
generation of additional atoms that should not be there.
I have attached the input and the CIF file of MWW zeolite, one
structure where the problem arises. The number of atoms in the cell
should be 216. However, the output of the calculation tells me that
there are more atoms recognised by CP2K:
Total number of
- Atomic kinds: 2
- Atoms: 282
Obviously, the calculation is doomed to crash (and so it does!). There
are possible work-arounds, either using a rhombohedral setting when
possible, or exporting the structure as XYZ file (ATEN works nicely,
VESTA seems to generate additional atoms, too). However, I wanted to
bring this observation to your attention.
Best wishes
Michael
INP****************************************************
&FORCE_EVAL
METHOD Quickstep
&DFT
&PRINT
&V_HARTREE_CUBE
STRIDE 1 1 2
&END
&END
BASIS_SET_FILE_NAME ../BASIS_MOLOPT
POTENTIAL_FILE_NAME ../POTENTIAL
&MGRID
CUTOFF 400
&END MGRID
&QS
EPS_DEFAULT 1.0E-12
&END QS
&SCF
EPS_SCF 1.0E-6
SCF_GUESS ATOMIC
MAX_SCF 25
&OUTER_SCF
EPS_SCF 1.0E-6
MAX_SCF 4
&END
&OT
MINIMIZER DIIS
PRECONDITIONER FULL_ALL ! or FULL_SINGLE_INVERSE
ENERGY_GAP 0.001
&END
&END SCF
&XC
&XC_FUNCTIONAL PBE
&END XC_FUNCTIONAL
&END XC
&END DFT
&SUBSYS
&CELL
ABC 14.390 14.390 25.198
ANGLES 90.0 90.0 120.0
&END CELL
&TOPOLOGY
CONNECTIVITY OFF
COORD_FILE_FORMAT CIF
COORD_FILE_NAME MWW.cif
&END TOPOLOGY
&KIND Si
BASIS_SET DZVP-MOLOPT-SR-GTH
POTENTIAL GTH-PBE-q4
&END KIND
&KIND O
BASIS_SET DZVP-MOLOPT-SR-GTH
POTENTIAL GTH-PBE-q6
&END KIND
&END SUBSYS
&END FORCE_EVAL
&GLOBAL
PROJECT MWW
PRINT_LEVEL MEDIUM
RUN_TYPE ENERGY_FORCE
&END GLOBAL
CIF****************************************************
data_MWW
#**************************************************************************
#
# CIF taken from the IZA-SC Database of Zeolite Structures
# Ch. Baerlocher and L.B. McCusker
# Database of Zeolite Structures: http://www.iza-structure.org/databases/
#
# The atom coordinates and the cell parameters were optimized with
DLS76
# assuming a pure SiO2 composition.
#
#**************************************************************************
_cell_length_a 14.3900(0)
_cell_length_b 14.3900(0)
_cell_length_c 25.1980(0)
_cell_angle_alpha 90.0000(0)
_cell_angle_beta 90.0000(0)
_cell_angle_gamma 120.0000(0)
_symmetry_space_group_name_H-M 'P 6/m m m'
_symmetry_Int_Tables_number 191
_symmetry_cell_setting hexagonal
loop_
_symmetry_equiv_pos_as_xyz
'+x,+y,+z'
'-y,+x-y,+z'
'-x+y,-x,+z'
'-x,-y,+z'
'+y,-x+y,+z'
'+x-y,+x,+z'
'-y,-x,+z'
'-x+y,+y,+z'
'+x,+x-y,+z'
'+y,+x,+z'
'+x-y,-y,+z'
'-x,-x+y,+z'
'-x,-y,-z'
'+y,-x+y,-z'
'+x-y,+x,-z'
'+x,+y,-z'
'-y,+x-y,-z'
'-x+y,-x,-z'
'+y,+x,-z'
'+x-y,-y,-z'
'-x,-x+y,-z'
'-y,-x,-z'
'-x+y,+y,-z'
'+x,+x-y,-z'
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
O1 O 0.6667 0.3333 0.0000
O2 O 0.5448 0.2724 0.0850
O3 O 0.3953 0.1060 0.1374
O4 O 0.5447 0.2724 0.1890
O5 O 0.6667 0.3333 0.2739
O6 O 0.3869 0.0000 0.2238
O7 O 0.5000 0.0000 0.1419
O8 O 0.5000 0.0000 0.3058
O9 O 0.3935 0.1052 0.3101
O10 O 0.5453 0.2726 0.3593
O11 O 0.3520 0.1760 0.3986
O12 O 0.1821 0.0000 0.4302
O13 O 0.2989 0.1495 0.5000
Si1 Si 0.4696 0.2348 0.1370
Si2 Si 0.4198 0.2099 0.3443
Si3 Si 0.2540 0.1270 0.4401
Si4 Si 0.3927 0.0000 0.1601
Si5 Si 0.3927 0.0000 0.2876
Si6 Si 0.6667 0.3333 0.0637
Si7 Si 0.6667 0.3333 0.2101
Si8 Si 0.6667 0.3333 0.3377
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