Development of a graphical interface for the Rietveld refinement programDBWS

The DBWS program, the latest version of which is 9807a (Young et al., 1999), an upgraded version of DBWS-9411, described by Young et al. (1995), is written in Fortran and can carry out Rietveld re®nements using digitized data (from a neutron or X-ray diffractometer) stored in a text ®le. It also requires an Input Control File (ICF), constructed by the user, which stores information about the material and program execution. The ICF is a text ®le that contains crystallographic information about the material and program settings in lines and columns. Given the size of the input ®le needed by DBWS, compiling it can be confusing, dif®cult and time consuming (an ICF for quartz plus alumina, which has only two phases, uses an ICF with more than 60 lines). Most users edit new ICFs by opening previously used ®les in a non-formatted text editor (such as Microsoft Notepad or DOS Edit) and then substituting the old values for new ones. Editing these ®les manually can be confusing because the user needs to know the placement of each parameter in the ICF; furthermore, small errors in the format of the ICF may cause problems when the program runs. After the program has run, a text ®le containing the re®ned data is returned, along with, optionally, a binary ®le that is used to plot the diffraction pattern using a graphics program such as DMPlot (Marciniak, 1997). To solve the aforementioned problems, a graphical interface for DBWS (which works with versions 9411 and 9807 and runs under Windows 95/98/NT) has been developed. Known as DBWS Tools, the program makes DBWS much easier to use and manages each step of the process, from the creation of the ICF to the plotting of the diffraction pattern using the external program DMPlot. In this way, the user need not consult the program manual every time a new sample is analysed (because the meaning of each data ®eld is shown on screen) and the entire process is much faster and user-friendly.