{"id":1831,"date":"2013-02-20T11:36:08","date_gmt":"2013-02-20T19:36:08","guid":{"rendered":"http:\/\/blogs.reed.edu\/shusterman_lab\/?p=1831"},"modified":"2014-03-18T10:14:49","modified_gmt":"2014-03-18T17:14:49","slug":"spartan-tip-symmetry-errors","status":"publish","type":"post","link":"https:\/\/blogs.reed.edu\/shusterman_lab\/2013\/02\/spartan-tip-symmetry-errors\/","title":{"rendered":"Spartan tip &#8211; Symmetry errors"},"content":{"rendered":"<p>Spartan automatically examines models for symmetry. When it finds symmetry elements, it applies these in subsequent calculations. For example, if you build &#8216;flat&#8217; NH3 (possible point groups: Cs, C3v, D3h, etc.) and calculate its equilibrium geometry, you will end up with a flat &#8216;minimum&#8217;. In other words, your final model won&#8217;t be a minimum at all. Here are some tips for dealing with symmetry, wanted and unwanted:<\/p>\n<ul>\n<li>turning off symmetry constraints\n<ul>\n<li>uncheck the <strong>Symmetry<\/strong> box in <strong>Setup: Calculations<\/strong><\/li>\n<li>adjust an atom (or group) position so that the initial model is less symmetric (if Spartan lists the point group as C1, no symmetry has been detected)<\/li>\n<\/ul>\n<\/li>\n<li>&#8220;&lt;point group&gt; slipped through&#8221; error message prevents the desired calculation &#8211; either uncheck the <strong>Symmetry<\/strong> box (see above) or <strong>Minimize<\/strong> a few times to reach a higher symmetry model (this can be a disaster so remember that you can use <strong>Undo<\/strong> to reverse one <strong>Minimize<\/strong>)<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Spartan automatically examines models for symmetry. When it finds symmetry elements, it applies these in subsequent calculations. For example, if you build &#8216;flat&#8217; NH3 (possible point groups: Cs, C3v, D3h, etc.) and calculate its equilibrium geometry, you will end up&nbsp;&hellip; <a href=\"https:\/\/blogs.reed.edu\/shusterman_lab\/2013\/02\/spartan-tip-symmetry-errors\/\">finish&nbsp;reading&nbsp;Spartan tip &#8211; Symmetry errors<\/a><\/p>\n","protected":false},"author":55,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[27,30],"class_list":["post-1831","post","type-post","status-publish","format-standard","hentry","category-spartan-howto","tag-spartan","tag-symmetry"],"_links":{"self":[{"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/posts\/1831","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/users\/55"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/comments?post=1831"}],"version-history":[{"count":3,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/posts\/1831\/revisions"}],"predecessor-version":[{"id":1845,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/posts\/1831\/revisions\/1845"}],"wp:attachment":[{"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/media?parent=1831"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/categories?post=1831"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.reed.edu\/shusterman_lab\/wp-json\/wp\/v2\/tags?post=1831"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}