DASH represents a major step forward in the rapidly evolving area of crystal structure determination from powder diffraction data. CCDC and CCLRC (the UK Council for the Central Laboratory of the Research Councils) are collaborating to distribute and develop DASH, a software package written by Prof. Bill David and Dr. Kenneth Shankland at the Rutherford Appleton Laboratory, U.K. DASH implements a global optimisation approach to structure solutions.

DASH is able to:

• Solve structures from indexed synchrotron and monochromatic laboratory X-ray powder data
• Solve the crystal structures of molecules comprising up to 16 flexible torsion angles and more than 40 non-hydrogen atoms
• Handle salt systems, solvates, and structures with more than one molecule in the asymmetric unit
• Perform rigid-body Rietveld refinement
• Handle up to 300 atoms in a structure

DASH features:

• An easy to use interface, supported on Windows operating systems
• Automatic background fitting and subtraction
• Peak fitting with an asymmetry-corrected Voigt function
• Links to indexing packages DICVOL and McMaille
• Quick and easy profile fitting
• A highly efficient simulated annealing algorithm that adjusts a trial molecular structure within an indexed cell, in order to maximise the agreement with the intensities extracted during the profile fit
• Semi-automated Rietveld refinement using TOPAS, GSAS or RIETAN, accessed directly from the DASH interface
• A specially-developed version of Mercury, which contains more advanced functionality than in the free version, to aid comparison of solutions

DASH can now also be run in batch mode either on a single computer, multi-core processor or a GRID network. For further information about setting up DASH on a GRID network, see http://www.gdash.info/.

DASH tutorial 1 is available in Japanese, please follow the link below:

For a free evaluation of DASH, normally available for those interested in purchase, please contact CCDC.