Dear Rietveld/SDPD users: The Derivative Difference Minimization (DDM) program is now freely available via the web:
http://krsk.info/icct/en/cont/persons/sol/ddm.html The program is designed for crystal structure analysis from powder diffraction data by making use of either Rietveld or Derivative Difference Minimization method [L.A. Solovyov, J. Appl. Cryst. 37 (2004) 743-749]. In the DDM method the refinement is aimed not at minimizing the absolute difference between the experimental and calculated profiles but at minimizing the oscillations (or curvature) of the difference curve. The squared values of the difference curve derivatives are used in DDM as a measure of the difference curvature. The main advantage of this method is that it does not require the background line modeling or approximations. Eliminating the systematic errors caused by inadequate background definitions, DDM allows structure refinemet with increased stability and precision. Enjoy the freedom from the "background headache"! Your comments and suggestions are welcome. Best regards, Leonid Solovyov ******************************************************** Leonid A. Solovyov Institute of Chemistry and Chemical Technology K. Marx av., 42 660049, Krasnoyarsk Russia Phone: +7 3912 495663 Fax: +7 3912 238658 E-mail: [EMAIL PROTECTED] http://krsk.info/icct/en/cont/persons/sol ******************************************************* __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
