From andrius.merkys at gmail.com Mon Jun 2 14:20:03 2025 From: andrius.merkys at gmail.com (Andrius Merkys) Date: Mon, 2 Jun 2025 14:20:03 +0300 Subject: [Cod-bugs] Programmatic Access to COD Data for Acentric Structures In-Reply-To: References: Message-ID: <8f37295a-7dbb-41b8-8d22-06fbb206f6fd@gmail.com> Dear Jason, On 2025-05-29 16:25, Jia, Qiming wrote: > I?m a research student currently working on a project that requires > downloading and processing crystallographic data from the COD, > specifically focusing on non-centrosymmetric (acentric) structures for > machine learning purposes. > While trying to automate the search using |search.php|, I encountered > difficulties?my script expected JSON responses, but it seems this > endpoint is not designed for API use. I?ve explored the documentation > but couldn?t find a confirmed method to programmatically filter or > retrieve structures based on space groups or symmetry properties. Please refer to COD Wiki page on the usage of search API [1]. You can use result.php as an endpoint emitting JSON-formatted output. You can query on Hermann-Mauguin space group symbol or space group number. I believe this should work in your case, you will just have to query for all acentric space groups separately. You may as well use COD OPTIMADE [2] interface, its base URL is at [3]. Be sure to use v1.2.0, as prior to this version there were no symmetry-related properties supported by OPTIMADE standard. Hope this helps, Andrius [1] https://wiki.crystallography.net/RESTful_API/ [2] https://www.optimade.org [3] https://www.crystallography.net/cod/optimade/v1.2.0/ -- Andrius Merkys Vilnius University Institute of Biotechnology, Saul?tekio al. 7 LT-10257 Vilnius, Lithuania -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.