TRANSFORM
2.3 - TRANSFORM - Transformation of Model and Data Files
This program allows the user to transform the unit cell
(with errors), the reflection indices (and if present the direction cosines),
the atomic coordinates and the anisotropic thermal parameters according to
a chosen transformation matrix R. A new model file NEW.INS and reflection file NEW.HKL
are written. A number of standard transformation matrices are available, but the
user can type in any matrix of choice. If the determinant of R is negative, the
cell volume is reported as negative, indicating that the resultant cell is
not right-handed. A new space group may be chosen from the list of 530
standard and non-standard settings. For an explanation of the various settings see
here.
For instance, suppose a user has collected data and refined a structure in the non-standard
orthorhombic space group C2cb, and wishes to transform the structure to the standard
setting. Looking down the list of space groups in
the TRANSFORM menu shows that C2cb is space group #41 with setting -cba.
To perform the transformation, the user merely needs to select the -cba matrix button, and
then choose the standard setting for this spacegroup, which is Aba2. Clicking the OK button
then gives transformed set (NEW.INS, NEW.HKL etc),which may be used for refinement without
any further changes.
The TEST button allows the user to see the result of applying the matrix to the
input cell.