Cambridge Structural Database

Cambridge Structural Database

Content
Description	Molecular structure elucidation X-ray crystallography Cheminformatics Metalorganic Organometallic
Contact
Research center	Cambridge Crystallographic Data Centre
Access
Data format	.cif
Website	.uk.ac.cam.ccdcwww
Web service URL	.uk.ac.cam.ccdcwebcsd
Tools
Web	WebCSD
Standalone	CSD System PreQuest CSD (the database) ConQuest Mercury IsoStar Mogul
Miscellaneous

The Cambridge Structural Database (CSD) is both a repository and a validated and curated resource for the three-dimensional structural data of [1]). The CSD is overseen by the not-for-profit incorporated company called the Cambridge Crystallographic Data Centre, CCDC.

The CSD is widely recognized as the world’s repository for small-molecule organic and metal-organic crystal structures, and has become an essential resource to scientists around the world. Structures deposited with CCDC are made publicly available for download at the point of publication or at consent from the depositor. They are also scientifically enriched and included in the Cambridge Structural Database (CSD) which underpins a range of software solutions offered by CCDC. Targeted subsets of the CSD are also freely available to support teaching and other activities.^[2]

History

The University of Cambridge. From 1965, the group began to collect published bibliographic, chemical and crystal structure data for all small molecules studied by X-ray or neutron diffraction. With the rapid developments in computing taking place at this time, this collection was encoded in electronic form and became known as the Cambridge Structural Database (CSD).

The CSD was one of the first numerical scientific databases to begin operations anywhere in the world, and received academic grants from the UK Office for Scientific and Technical Information and then from the UK . These funds, together with subventions from National Affiliated Centres, enabled the development of the CSD and its associated software during the 1970s and 1980s. The first releases of the CSD System to the USA, Italy and Japan occurred in the early 1970s. By the early 1980s the CSD System was being distributed in more than 30 countries worldwide. As of 2014, the CSD System is now distributed to academics in 70 countries worldwide.

During the 1980s, interest in the CSD System from pharmaceutical and agrochemicals companies increased significantly. This led to the establishment of the CCDC as an independent company in 1987, with the legal status of a non-profit charitable institution, and with its operations overseen by an international Board of Governors. The CCDC moved into purpose-built premises on the site of the University Department of Chemistry in 1992.

Dr Kennard retired as Director in 1997 and was succeeded by Dr David Hartley (1997-2002) and Dr Frank Allen (2002-2008). Dr Colin Groom was appointed as Executive Director from 1 October 2008.

CCDC software products have now diversified to make maximum use of crystallographic data in applications in the life sciences and crystallography. Much of this software development and marketing is now carried out by CCDC Software Limited (founded in 1998), a wholly owned subsidiary which covenants all of its profits back to the CCDC.

Although the University of Cambridge, and is a University Partner Institution that is qualified to train postgraduate students for higher degrees (PhD, MPhil).

The CCDC established US applications and support operations in the USA in October 2013 at Rutgers, the State University of New Jersey, where it is co-located with the RCSB Protein Data Bank

Contents

The CSD is continually updated with new structures (>50,000 new structures each year)^[3] and with improvements to existing entries. Entries (structures) in the repository are released for public access shortly after the corresponding entry has appeared in the peer-reviewed scientific literature.

As of 6 January 2014, the top 25 scientific journals in terms of publication of structures in the CSD repository were:

1. 700455119000000000055,119 structures were reported in Inorg.Chem.

2. 700441850000000000041,850 structures were reported in Dalton & J.Chem.Soc.,Dalton Trans.

3. 700441761000000000041,761 structures were reported in Organometallics

4. 700438148000000000038,148 structures were reported in Acta Crystallogr.,Sect.E

5. 700435943000000000035,943 structures were reported in J.Am.Chem.Soc.

6. 700425062000000000025,062 structures were reported in J.Organomet.Chem.

7. 700424676000000000024,676 structures were reported in Acta Crystallogr.,Sect.C

8. 700422552000000000022,552 structures were reported in Inorg.Chim.Acta

9. 700421663000000000021,663 structures were reported in Chem.Commun. & J.Chem.Soc.

10. 700418454000000000018,454 structures were reported in Polyhedron

11. 700418089000000000018,089 structures were reported in Angew.Chem.,Int.Ed.

12. 700417303000000000017,303 structures were reported in Chem.-Eur.J.

13. 700416747000000000016,747 structures were reported in Eur.J.Inorg.Chem.

14. 700416134000000000016,134 structures were reported in J.Org.Chem.

15. 700413756000000000013,756 structures were reported in Acta Crystallogr.,Sect.B

16. 700412228000000000012,228 structures were reported in Z.Anorg.Allg.Chem.

17. 700412069000000000012,069 structures were reported in Cryst.Growth Des.

18. 700411614000000000011,614 structures were reported in CrystEngComm

19. 700410312000000000010,312 structures were reported in Tetrahedron

20. 70038995000000000008,995 structures were reported in Tetrahedron Lett.

21. 70038597000000000008,597 structures were reported as Private Communication to the CSD

22. 70038097000000000008,097 structures were reported in Organic Letters

23. 70037280000000000007,280 structures were reported in J.Mol.Struct.

24. 70036847000000000006,847 structures were reported in Z.Naturforsch.,B

25. 70035807000000000005,807 structures were reported in Eur.J.Org.Chem.

These 25 journals account for 499,109 of the 686,944 or 72.7% of the structures in the CSD.

These data show that most structures are determined by X-ray diffraction, with less than 1% of structures being determined by neutron diffraction or powder diffraction. The number of error-free coordinates were taken as a percentage of structures for which 3D coordinates are present in the CSD.

The significance of the structure factor files, mentioned above, is that, for CSD structures determined by X-ray diffraction that have a structure file, a crystallographer can verify the interpretation of the observed measurements.

Growth trend

Note: data for 1923-1964 are aggregated together in the last line of the table.

File format

The primary file format for CSD structure deposition, adopted around 1991, is the "Crystallographic Information file" format, CIF.^[7]

The deposited CSD files can be downloaded in the CIF format. The validated and curated CSD files can be exported in a wide range of formats, including CIF, MOL, Mol2, PDB, SHELX and XMol, using tools in the CSD System.

The CCDC and assigned the deposition number 'CCDC-991327.' This allows free public access to the data as deposited. From the deposited data, selected information is extracted to prepare the validated and curated CSD entry which was assigned the refcode 'MITGUT'. The validated and curated entry is included in the CSD System and WebCSD distributions, with availability restricted to those making appropriate contributions.

Viewing the data

The structure files may be viewed using one of several open source computer programs such as Jmol. Some other free, but not open source programs include MDL Chime, Pymol, UCSF Chimera, Rasmol, WINGX,^[8] and the CCDC provides a free version of its molecule visualization program Mercury.

See also

• Crystallographic database
• Protein structure

References