I agree with Alan, and may add that searching for isomorphous structures can help and happens very often. Complex anions may replace single atom anions etc. For the inorganic world I strongly recommend the Pearson Crystal Data which allows for nice combined search using for example atomic coordination.
Radovan Radovan Cerny Laboratoire de Cristallographie, DQMP Université de Genève 24, quai Ernest-Ansermet CH-1211 Geneva 4, Switzerland Phone : [+[41] 22] 37 964 50, FAX : [+[41] 22] 37 961 08 mailto : radovan.ce...@unige.ch<mailto:radovan.ce...@unige.ch> URL : http://www.unige.ch/sciences/crystal/cerny/rcerny.htm De : rietveld_l-requ...@ill.fr [mailto:rietveld_l-requ...@ill.fr] De la part de Alan Hewat Envoyé : mardi 10 janvier 2017 16:54 À : Shay Tirosh <stiro...@gmail.com> Cc : rietveld_l@ill.fr Objet : Re: How much COD and PDF database gives the complete known structures? It depends on what you want. If you want to identify a powder pattern you probably want to use the PDF, which may also help with the structure. If you want to find a particular structure, you can try COD. If you are planning a structure determination and want to be sure that it hasn't already been done, you should use ICSD (inorganic) or CCSD (organic) if the material contains carbon because those databases are exhaustive. If possible use all available databases, since it is expensive to do an experiment before doing a thorough literature search. Don't forget Google Scholar. Don't rely on databases; use them to find the original papers - then read them, don't just add them to your reference list. You should also consider how the database is searched. A simple search on the supposed formula may miss the structure described with a slightly different formula, or may miss isomorphous structures that may be almost as useful as the structure you require. Alan. On 10 January 2017 at 16:12, Shay Tirosh <stiro...@gmail.com<mailto:stiro...@gmail.com>> wrote: Dear retrievers I wander the followings: 1. How much COD and PDF overlaps? 2. What I am missing if I only search in COD and PDF? Are there any reviews addressing those questions ? Thank you from advance Shay -- _________________________________________________ Dr. Shay Tirosh Institute for Nanotechnology & Advanced Materials Bar Ilan University Ramat Gan, 52900 Israel Phone: +972-(0)30-531-7320 Mobile: +972-(0)54-8834533<tel:+972%2054-883-4533> Email: stiro...@gmail.com<mailto:stiro...@gmail.com> _________________________________________________ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Please do NOT attach files to the whole list <alan.he...@neutronoptics.com<mailto:alan.he...@neutronoptics.com>> Send commands to <lists...@ill.fr<mailto:lists...@ill.fr>> eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -- ______________________________________________ Dr Alan Hewat, NeutronOptics, Grenoble, FRANCE <alan.he...@neutronoptics.com<mailto:alan.he...@neutronoptics.com>> +33.476.98.41.68 http://www.NeutronOptics.com/hewat ______________________________________________
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Please do NOT attach files to the whole list <alan.he...@neutronoptics.com> Send commands to <lists...@ill.fr> eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
