XtalComp: Compare crystal structures

XtalComp Web Interface: Enter POSCAR files

Paste a POSCAR file into each of the following boxes and hit "Compare" to let XtalComp determine if they describe the same structure.


Tolerance for position / length comparisons. Same units as cell matrix. (default = 0.05):
Angular tolerance for lattice comparisons (default = 0.25 degrees):

Notes:

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