XtalComp: Compare crystal structures
Notes:
-
The POSCAR format is specified here.
-
Each structure must have the same number of atoms, and the
order of the atom type counts (line 6) must be the same in each
POSCAR.
-
Update: you may now compare different crystals with different formula
units (e. g. Ti1O2 and Ti2O4). The crystals will be reduced to their
primitive form using functions from spglib before the comparison.
However, the order of atoms must still match.
About:
XtalComp is an algorithm developed for the
genetic
algorithm XtalOpt.
It will determine if two crystal structure descriptions refer to the
same underlying structure, despite choice of unit cell vectors,
rotations, reflections, translations, and numerical
noise. The source code is available under
the "New" BSD
open source license
from our Github
repository. The algorithm has
been fully
described in an academic journal
(free
preprint).
Example:
Try the following two POSCAR files for an example.
Example POSCAR 1:
Title
1
3.16227766 0.00000000 0.00000000
-0.94868330 4.13521463 0.00000000
-0.94868330 -0.21764288 4.12948321
2 1 1
Direct
0.44484437 0.39707990 0.29516526
0.94291143 0.39851556 0.79211122
0.44696910 0.89705880 0.79428583
0.94477875 0.39618846 0.29352825
Example POSCAR 2:
Title
1
6.00000000 0.00000000 0.00000000
1.00000000 3.00000000 0.00000000
2.00000000 -3.00000000 3.00000000
2 1 1
Direct
0.00000000 0.00000000 0.00000000
0.00000000 0.00000000 0.50000000
0.50000000 0.00000000 0.00000000
0.00000000 0.50000000 0.00000000