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What is a non-CSD structure?


Non-CSD structures are structures that do not currently meet the criteria for inclusion in the Cambridge Structural Database (CSD) or the Inorganic Crystal Structure Database (ICSD) or that have not yet been linked to the ICSD number. They are not curated into the main database but are still available from our free Access Structures service. This ensures as much data as possible can be shared with the community without changing the remit of the CSD or compromising its integrity.

The CSD is a database of organic and metal-organic experimental 3D crystal structures from X-ray and neutron diffraction structures. Non-CSD structures include, for example, any calculated structures that have been deposited at the CCDC. For more information on what can be deposited at CCDC and what the criteria is for inclusion into the CSD please see our FAQ: What are the criteria for deposition to the CCDC?

There are currently around 13,000 non-CSD structures stored at CCDC and the majority of these are calculated structures and they include all the calculated structures from the sixth CCDC blind test. The remaining non-CSD structures include protein structures, inorganic structures or incommensurate structures that have been deposited at the CCDC and assigned CCDC numbers but have not been curated into the CSD. Curated versions of these structures are available in the relevant external databases where appropriate. An example of a non-CSD structure can be found here.

Non-CSD structures can be identified by:

  • Having ‘Non-CSD Structure’ in the title banner -
  • A different colour (red) title banner

This differs from a CSD entry (such as this example) which has a CSD refcode in the blue title banner, or an entry from the Inorganic Crystal Structure Database (ICSD), such as this, which has ' ICSD Structure' in the black title banner

Non-CSD structures are not curated into the main CSD and as a result will not have a CSD refcode or compound name. Any 2D chemical diagrams that are available for non-CSD entries have been automatically generated and have not gone through our manual curation checks. They are not included in the CSD that is distributed with the CSD Portfolio and are therefore not available through programs such as ConQuest, our CSD Python API and are not included in Mogul libraries generated from the CSD.

Non-CSD structures do however still receive a deposition number which can be added to manuscripts pre-publication. If deposition number associated with an article are published then these can be linked to as normal using our Access Structures service enabling anyone to view and retrieve the relevant data from the CCDC.