Download User Guide and Tutorials - The Cambridge Crystallographic Data


Choose Very high similarity by clicking the relevant radio button under Level of
Geometric Similarity Required and then click Next.

At this point you can choose one or more geometric parameters to record for
each of the matched packing features that are found. Select the two chlorine
atoms in the 3D view and click Add Distance > to choose this parameter, then
click Next to continue.

Here the structures you wish to search for the defined packing feature must be
selected. Add the full Cambridge Structural Database to the Selected Structures
section by choosing the CSD from the list of available structures and clicking on
the blue right-hand arrow button.

Click Next and then specify the following database search filters: 3D coordinates
determined, Not disordered, No errors, Not polymeric, R-factor <= 0.1, Only
organics.

Click Next followed by Start Search to run the packing feature search, hits will
now start appearing in the Searches tab of the Structure Navigator.
4. Study list of search results
362

Take a look at the list of hits shown in the Structure Navigator. There will be
over 90 structures found with a similar packing feature in the database. Click on
the RMS button at the top of the results list and the results will be ranked in
order of the RMS deviation between the search packing feature and the hit
packing feature. You will see that the halogen to halogen distance is also shown
in the results list for each match.

A glance at the structures with low RMS values (i.e. very similar packing
features) shows that there are a number of other refcodes starting with CLBZAP,
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