From randolph.williams at mail.mcgill.ca Thu Sep 21 16:59:07 2017 From: randolph.williams at mail.mcgill.ca (Randy Williams) Date: Thu, 21 Sep 2017 08:59:07 -0500 Subject: [Cod-bugs] Querying COD Message-ID: Hello, I would like to find information on how to look up diffraction information (d-spacings and relative intensities) through querying the COD. I am attempting to construct some custom search match software for my lab but I am unable to locate diffraction data in the COD. Please advice when convenient. Best, Randy Williams -------------- next part -------------- An HTML attachment was scrubbed... URL: From grazulis at ibt.lt Thu Sep 21 19:08:52 2017 From: grazulis at ibt.lt (=?UTF-8?Q?Saulius_Gra=c5=beulis?=) Date: Thu, 21 Sep 2017 19:08:52 +0300 Subject: [Cod-bugs] Querying COD In-Reply-To: References: Message-ID: Dear Randy, On 2017-09-21 16:59, Randy Williams wrote: > I would like to find information on how to look up diffraction > information (d-spacings and relative intensities) through querying the > COD. I am attempting to construct some custom search match software for > my lab but I am unable to locate diffraction data in the COD. Please > advice when convenient. Diffraction data in COD is in the hkl/ tree: http://www.crystallography.net/cod/hkl/ it can also be found in the appropriate Subversion repository branch. These are experimental Fobs data, whenever authors have provided them; they are not available for all structures. The d-spacings are easily calculated from the unit cell data, we do not provide them. Unit cell is specified in each coordinate and Fobs (.hkl) file. Calculating relative intensities is more tricky, we do not have them on-line but one can do that by appropriate summation of atomic structure factors or by FFT. I would recommend you some text on crystallographic computing, e.g. C. Giaccovazzo "Fundamentals of Crystallography" is pretty advanced but will answer all (or most) of your questions (https://global.oup.com/academic/product/fundamentals-of-crystallography-9780199573660?cc=lt&lang=en&). Hope this helps. Sincerely, Saulius -- Dr. Saulius Gra?ulis Vilnius University Institute of Biotechnology, Saul?tekio al. 7 LT-10257 Vilnius, Lietuva (Lithuania) fax: (+370-5)-2234367 / phone (office): (+370-5)-2234353 mobile: (+370-684)-49802, (+370-614)-36366