Structure Relations

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Structure Relations

Structures Relations

The transformation matrix connecting the group-subgroup related structure descriptions is calculated by first finding a compatible affine normalizer with respect to the lattice parameters and possible transformation matrixes for the given group-subgroup fetched from the database.

Once the lattice-compatible transformation is derived, the Euclidean normalizers of the subgroup are applied to find the most suitable transformation, this time also taking into account the atomic positions.

Structure descriptions given in non-standard settings:

STRUCTURE RELATIONS work with structure descriptions defined in standard setting. If your structure descriptions are given in non-standard settings, you can convert them to standard setting via the CIF2TRANS or SETSTRU or TRANSTRU tools.

High symmetry structure description
Structure Data [CIF format]
BCS Format		# Space Group ITA number 166 # Lattice parameters (lengths in angstroems and angles in degrees) 5.56 5.56 20.39 90 90 120 # Number of independent atoms in the asymmetric unit 5 # [atom type] [number] [WP] [x] [y] [z] Pb 1 3a 0 0 0 Pb 2 6c 0 0 0.2126 P 1 6c 0 0 0.4021 O 1 6c 0 0 0.329 O 2 18h 0.181 -0.181 0.096

Low symmetry structure description
Structure Data [CIF format]
BCS Format		# Space Group ITA number 15 # Lattice parameters (lengths in angstroems and angles in degrees) 13.80 5.691 9.42 90 102.3 90 # Number of independent atoms in the asymmetric unit 7 # [atom type] [number] [WP] [x] [y] [z] O 1 8f 0.643 0.030 0.392 O 2 8f 0.634 0.464 0.374 O 3 8f 0.642 0.280 0.612 O 4 8f 0.491 0.222 0.420 P 1 8f 0.599 0.241 0.447 Pb 1 4e 0 0.291 0.25 Pb 2 8f 0.317 0.309 0.352

Calculation parameters:
The tolerances are used to compare the differences between the high symmetry structure description transformed to the low symmetry structure description's setting and the given low symmetry structure description used as reference.
Enter the allowed lattice tolerance (a b c α β γ): (a,b,c are in Å while α, β, γ are in °, indicating the maximum allowed differences)
-Or- Enter the allowed tolerance for the lattice parameters' ratios:
	:	:	:
(The values entered are processed as the maximum allowed deviation from the ideal value of 1 should they coincide)
Enter the tolerance for the maximum difference in the position of matching atoms: Å

Calculation method:

The group-subgroup transformation matrices are automatically fetched from the database.

User defined transformation matrix :

Force a species match even if the two structure descriptions contain the same types of elements

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