The following release of the GUI WinCrystals 2000 Single Crystal Refinement software suite may be of interest to Rietveld users and developers. (Crystals can be freely downloaded off the internet from the addresses given below) Rietveld analysis is being used more for refinement of organic and organo-metallic phases. Making the style of interface incrporated inside the GUI CRYSTALS especially relevant in that many of these organic structures from powders (as noted previously by Armel) require the use of restraints/constraints to refine in a reasonable manner due to the number of atoms involved. The GUI Win CRYSTALS 2000 Single Crystal Refinement suite has some interesting ways of interacting with the structure while performing the refinement as the structure is always on the screen and options such as restraints, rigid bodies, automatic placement of hydrogen atoms, etc is quite trivial to do. It also has a "guided-refinement" to assist chemists who may be new to crystallography in refining routine structures in a solid way. (The closest equivalent of "guided-refinement" in Rietveld software would be the MAUD for Java by Luca Lutterotti and the commercial fundamental parameters based Rietvelds, BGMN and Topas) GUI WinCrystals 2000 Webpage: http://www.xtl.ox.ac.uk/ http://www.ccp14.ac.uk/ccp/web-mirrors/crystals/ http://ccp14.sims.nrc.ca/ccp/web-mirrors/crystals/ CCP14 Based Tutorial run-through area: http://www.ccp14.ac.uk/tutorial/crystals/ Example Refinement of an Organic Structure With Crystals (including automatic hydrogen placement) http://www.ccp14.ac.uk/tutorial/crystals/organic_refine.html ------------- Rietvelds mentioned: MAUD for Java: http://www.ing.unitn.it/~luttero/ http://www.ccp14.ac.uk/ccp/web-mirrors/lutterotti/~luttero/ BGMN (PC/UNIX): http://www.bgmn.de/ http://www.ccp14.ac.uk/ccp/web-mirrors/bgmn/ Topas Refer Bruker site: http://www.bruker-axs.com ----- Lachlan. -- Lachlan M. D. Cranswick Collaborative Computational Project No 14 (CCP14) for Single Crystal and Powder Diffraction Daresbury Laboratory, Warrington, WA4 4AD U.K Tel: +44-1925-603703 Fax: +44-1925-603124 E-mail: [EMAIL PROTECTED] Ext: 3703 Room C14 http://www.ccp14.ac.uk
