Chemical Structure Representation
There are two principal techniques for representing chemical structures in digital databases
- As connection tables / adjacency matrices / lists with additional information on bond (edges) and atom attributes (nodes), such as:
- MDL Molfile, PDB, CML
- As a linear string notation based on depth first or breadth first traversal, such as:
- SMILES/SMARTS, SLN, WLN, InChI
These approaches have been refined to allow representation of stereochemical differences and charges as well as special kinds of bonding such as those seen in organo-metallic compounds. The principal advantage of a computer representation is the possibility for increased storage and fast, flexible search.
Read more about this topic: Chemical Database
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