DASH: crystal structure solution from powder diffraction data

About DASH

DASH is a versatile and interactive package for solving crystal structures from powder diffraction data. DASH solves structures by simulated annealing of structural models to indexed diffraction data and features a helpful wizard to guide you through the entire structure solution process.

DASH accepts both synchrotron and monochromatic laboratory X-ray powder diffraction data in a wide variety of common file formats. The program has been successful in solving the structures of many systems of both academic and industrial interest. At the upper level of complexity, DASH has solved structures for molecules comprising up to 16 flexible torsion angles, more than 72 non-hydrogen atoms and up to six molecules in the asymmetric unit.

DASH has been successfully used to solve a diverse array of structure types including pharmaceutical compounds (e.g. naltrexone hydrochloride), salts (e.g. amodiaquinium dichloride dehydrate), solvates (e.g. chlorothiazide N,N-dimethylformamide solvate), semiconductors (e.g. lithium 1,8,15,22-tetraphenoxyphthalocyanine) and explosives (e.g. silver azide). DASH is also routinely applied to the solution of organometallic crystal structures, and has been used to solve inorganic crystal structures.

System Requirements and Installation

DASH runs under Windows 10 and 11. To install it go to https://github.com/ccdc-opensource/dash/releases and download and run the latest release installer.

Subscribers to the Cambridge Structural Database Portfolio benefit from direct links with Mogul for the automatic assessment and use of torsional restraints during structure solution. Biasing conformational searching towards torsion angle ranges commonly observed in crystal structures has been shown to give, on average, a 40% reduction in the number of moves required to solve the structure compared to unconstrained runs. This not only speeds up structure solution but can also make challenging problems tractable. For more information please visit the CCDC website or email CCDC.

Licensing

DASH is distributed under the MIT Licence.

Documentation

The DASH User Guide is provided in the dash project wiki. Tutorial material is provided in the tutorials folder. The examples directory contains examples.

It is recommended that new users work through the tutorials before using DASH for the first time.

Support

Since 2022, CCDC no longer provides support for DASH under the CSD Software Portfolio subscription. Users can file Issues in the GitHub repository. CCDC makes no commitment its staff will address any of these issues.

Acknowledgements

DASH has been developed and distributed in collaboration between the Science and Technology Facilities Council (STFC) at the ISIS Facility of the Rutherford Appleton Laboratory and CCDC Software Ltd. (CCDC).

We wish to acknowledge:

• the work by P. J. Brown, J. C. Matthewman and others in the development of the CCSL library
• A. J. Markvardsen, W. I. F. David, J. Johnston and K. Shankland for the ExtinctionSymbol program
• D. Louer and A. Boultif for the DICVOL programs

References

1. W. I. F. David, K. Shankland, J. van de Streek, E. Pidcock, W. D. S. Motherwell, J. C. Cole, J. Appl. Cryst., 39, 920-915, 2006
2. I. J. Bruno, J. C. Cole, M. Kessler, Jie Luo,W. D. S. Motherwell, L. H. Purkis, B. R. Smith, R. Taylor, R. I. Cooper, S. E. Harris, A. G. Orpen, J. Chem. Inf. Comput. Sci., 44, 2133-2144, 2004
3. E. Pidcock, J. van de Streek, M. U. Schmidt, Z. Krist., 222, 713-717, 2007
4. C. F. Macrae, I. J. Bruno, J. A. Chisholm, P. R. Edgington, P. McCabe, E. Pidcock, L. Rodriguez-Monge, R. Taylor, J. van de Streek, P. A. Wood, J. Appl. Cryst., 41, 466-470, 2008
5. A. J. Florence, N. Shankland, K. Shankland,W. I. F. David, E. Pidcock, X. Xu, A. Johnston, A. R. Kennedy, P. J. Cox, J. S. O. Evans, G. Steele, S. D. Cosgrove, C. S. Frampton, J. Appl. Cryst., 38, 249-259, 2005
6. K. Sugimoto, R. E. Dinnebier, M. Zakrzewski, J. Pharm. Sci., 96, 3316-3323, 2007
7. A. Llinàs, L. Fábián, J. C. Burley, J. van de Streek, J. M. Goodman, Acta Cryst., E62, o4196-o4199, 2006
8. P. Fernandes, K. Shankland, A. J. Florence, N. Shankland, A. Johnston, J. Pharm. Sci., 96, 1192-1202, 2007
9. R. P. Pandian, M. Dolgos,V. Dang, J. Z. Sostaric, P. M. Woodward, P. Kuppusamy, Chem. Mater., 19, 3545-3552, 2007
10. C. L. Schmidt, R. Dinnebier, U.Wedig, M. Jansen, Inorg. Chem., 46, 907-916, 2007
11. R. E. Dinnebier, A. Kowalevsky, H. Reichert, M. Jansen, Z. Krist., 222, 420-426, 2007
12. J. C. Burley, W. D. S. Motherwell, J. Maaranen, M. Ringwald, Acta Cryst., E63, m238-m240, 2007