SYSTEM-S DIRDIF
SYSTEM-S TOOLS
PLATON HOMEPAGE
DIRDIF/PATTY
Clicking on this button invokes the DIRDIF/PATTY program suite
for the structure determination of 'heavy atom' structures via
Patterson techniques.
DIRDIF/ORIENT
Clicking on this button invokes the DIRDIF/ORIENT program suite
for structure determination based on an orientation search with
a known structural fracment (model).
The model is assumed to be present as an ATMOD-file in
~USER/s/COMPOUND/.model.
When no such a file is found, the DIRDIF/ORBASE feature is started up
in the ASCII window in order to generate such a model.
Example:
- Startup the sdemo test-example with SYSTEM S in space group Pc (or
P21). Note: P21/c will not work for the centrosymmetric model we are
going to use.
- Continue until the suggested 'shelxl86' based phase determination.
- Click on ORNT (Next to the Dirdif field in the vertical menu at the
right)
- Answer the questions of DIRDIF/ORBASE. Choose either '19.11' (i.e.
Benzene) or 18.11 (Benzoquinone) as a model. and save/exit.
- A PLUTON drawing of the solved structure will pop-up.
- Acknowledge the isotropic refinement instruction.
- Click on ADDSYM to find out the real symmetry (P21/c). The result is
shown on the graphics window in RED: M/P-SPGR P21/c.
- Implement the newly found symmetry by clicking on TRMX. As a result
A new branch in the directory tree is created up to the point where
refinement can be continued.
09-may-2000 A.L.Spek