How to use ToposPro to work out a topology of a framework

Topology is a very important way of classifying the connectivity of framework materials but ToposPro, the standard software for topological analysis can be quite intimidating. I am no mathematical topologist or ToposPro expert, but here is a short guide for how to take a CIF and analyse the topology of its simplified net. Much more information is available from the ToposPro website and manual. If you would rather one of the experts deteremines the topology of your structure for you, the ToposPro team will now do this for you.

(1) Import a CIF

This is referred to as generating a database in the manual. Click on ‘Database->Import’ then find the CIF you wish to import and click open, then choose the database file name (which you can leave as default). Change the user code to 1 from 0. Detailed information can be found in Module 1 in the practical manual.

(2) Simplify the topology

This uses AutoCN (found in ‘Program->AutoCN’) and ADS (found in ‘Program->ADS’). First start and run AutoCN (default options are fine), then start ADS. Unselect all the checkboxes in common and topology, except for save simplified net, then run. You’ll need to choose which atoms will form the nodes of your simplified net (e.g. metal centres). This will generate a new database file with hopefully the correct connectivity. Check the new database file has the right coordination number by double clicking on its entry in ‘Compounds’ (the simplified ligand will be represented as Sc). This is Module 4 in the practical manual.

(3) Analyse the topology

With the new, simplified topology open, start ADS again. This time, unselect everything in common and topology except point symbols and classification. You will also need to increase Coord Seq and Max Ring to 10. Run ADS again, and once again select the nodes of your network. If you haven’t loaded the database of existing topologies (.ttd files) then ToposPro will prompt you to do so, which will take a little time. Once this is done then ToposPro will output the topology descriptors, for your consideration. This is Module 5 in the practical manual.

Happy Toposing!