What software do people use to successfully manipulate .cif files and get them to work with raspa? I've tried fairly simple things (like read in the FAU_SI.cif provided with raspa, convert it to P1, and export it back to .cif) and they seem to not work; sometimes with useful error messages and sometimes not. Besides Materials Studio which I don't have access to, what software works reliably? I've tried Avogadro and VESTA without success. They usually read each other's exported files or those included with raspa, but raspa does not read theirs. Does anyone have any tricks, hints, reports of idiosyncrasies, recommendations, or things to watch out for?
As an example (but I am really looking for general help), the FAU --> P1 in VESTA exercise above yielded the .cif shown below (and attached), but gave "ERROR in cif-file: no proper space group definition found" (after reporting tons of "unknown" lines) even though it has two lines relating to the space group. (Sorry: I couldn't get attachments to work).
#======================================================================
# CRYSTAL DATA
#----------------------------------------------------------------------
data_VESTA_phase_1
_chemical_name_common 'FAU'
_cell_length_a 24.34500
_cell_length_b 24.34500
_cell_length_c 24.34500
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_space_group_name_H-M_alt 'P 1'
_space_group_IT_number 1
loop_
_space_group_symop_operation_xyz
'x, y, z'
loop_
_atom_site_label
_atom_site_occupancy
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_adp_type
_atom_site_B_iso_or_equiv
_atom_site_type_symbol
O1 1.0 0.895800 0.104200 0.000000 Biso 1.000000 O
...
Thanks for any help.
Similar to my other post on .cif files, I'll report that I was only able to solve my .cif file problems by using the header from a working P1 .cif file (e.g. from the structures directory in the distribution), cutting out the coordinates, pasting in fractional coordinates for my system of interest, and modifying the cell parameters. I still do not know why some .cif files which work in other codes do not work in raspa, but it mentions somewhere in the manual or other documentation, that they can be tricky.
Hi,
I faced the same problem too, even when I used Material Studio to convert the original .cif file to P1 symmetry.
I have one query, is it necessary to always convert the input structure to P1 symmetry for RASPA or we can also provide the original symmetry?
Thanks in advance!
Warm regards,
Somananda
P1 is safer. Specifying the spacegroup is not unique, unless the Hall-symbols are used. Materials Studio and other codes do not do that. So, yes you can use symmetry, but if it does not work, it is usually because the space group is not set properly.
Using P1 avoids these issues.