ENHANCEMENTS OF THE SAINT INTEGRATION PROGRAM FOR CCD DETECTORS

M.R. Pressprich¹ and E.R. Hovestreydt²

¹Bruker-AXS Inc., 6300 Enterprise Lane, Madison, WI 53719, Email: mpressprich@bruker-axs.com
²Bruker-AXS GmbH, Rheinbrückenstr, 76181 Karlsruhe Email: eric.hovestreydt@bruker-axs.de

Extracting accurate data from single crystals with a CCD (or multi-wire) detector requires sophisticated software such as the latest incarnation of SAINT.

Besides sophisticated integration algorithms, a friendly user interface and graphical presentation of results are all of importance to the crystallographer - chemical or biological.

Our recent efforts in developing new integration algorithms have emphasised the need to tailor SAINT for analysing both sparse images containing a wide range of reflection intensities (chemical samples) as well as dense images with predominantly weak reflection intensities (biological samples).

In terms of integration algorithms, we have developed a least-squares profiling method in addition to the previous simple summation method. The two methods complement each other and can be used simultaneously - least-squares profiling works well for weak reflections while the simple summation method is appropriate for stronger reflections.

A new interface to SAINT, SAINT+, eliminates the need to manually enter detector parameters and also presents tailored menu interfaces for protein or small molecule refinements. Graphical tools, such as a mouse-orientable display of all thresholded reflections, are being developed to quickly identify mosaic, split, twinned or modulated crystals.