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Why is my search taking so long?


This is probably due to limitations in the CSD search engine. The most common types of slow searches are:

  • Substructure searches for groups that contain symmetry (e.g. t-butyl); these can take a very long time indeed, especially if 3D parameters are being calculated.
  • Substructure searches for groups that contain only the most common elements (C,N,O) and are connected by single or Any bond types.
  • Substructure searches for large (>12-membered) rings, especially if they are carbocyclic.
  • Searches for nonbonded interactions especially for patterns involving more than one interaction.
  • Some text searches.​