{"id":5815,"date":"2014-08-18T11:47:42","date_gmt":"2014-08-18T10:47:42","guid":{"rendered":"https:\/\/blogs.nature.com\/thescepticalchymist\/?p=5815"},"modified":"2014-08-18T11:47:42","modified_gmt":"2014-08-18T10:47:42","slug":"jaws-up-close","status":"publish","type":"post","link":"https:\/\/blogs.nature.com\/thescepticalchymist\/2014\/08\/jaws-up-close.html","title":{"rendered":"Jaws up close"},"content":{"rendered":"<p><em>Posted on behalf of Leonie Mueck, Associate Editor, Nature.<\/em><\/p>\n<p>&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8211;<\/p>\n<p>In <a href=\"https:\/\/www.nature.com\/nchem\/journal\/v6\/n3\/full\/nchem.1883.html\" target=\"_blank\">Jaws up close<\/a>, I highlighted <a href=\"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/ange.201307689\/abstract\" target=\"_blank\">an article<\/a> from a group of researchers led by Zhongchang Wang at Tohoku University on a new electron microscopy technique that achieved atomic resolution of the fluoroapatite structure in shark teeth without damaging the sample. A technical comment has now been published, which refutes the proposed bonding situation in fluoroapatite. On the basis of density functional theory calculations, Wang <em>et al.<\/em> had claimed that the Ca-F bond in fluoroapatite is covalent, which could be crucial in understanding why shark teeth are so healthy.<\/p>\n<p>Based on further calculations and bonding analysis, Antti Karttunen from Aalto University, Finland, and Florian Kraus, from Technische Universitaet Muenchen, Germany, now show <a href=\"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/anie.201402426\/abstract\" target=\"_blank\">in their comment<\/a> that this conclusion is unsubstantiated. Rather, the Ca-F bond should be seen as ionic which rules out its strengthening function in shark teeth.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u2014\u2014\u2014\u2014\u2014\u2014\u2014\u2013&nbsp; <a href=\"https:\/\/blogs.nature.com\/thescepticalchymist\/2014\/08\/jaws-up-close.html#more-5815\" class=\"more-link\"> &hellip; Read more<\/a> <a href=\"https:\/\/blogs.nature.com\/thescepticalchymist\/2014\/08\/jaws-up-close.html\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":541,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20,11],"tags":[],"class_list":["post-5815","post","type-post","status-publish","format-standard","hentry","category-nchem-research-highlights","category-other-authors"],"_links":{"self":[{"href":"https:\/\/blogs.nature.com\/thescepticalchymist\/wp-json\/wp\/v2\/posts\/5815","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.nature.com\/thescepticalchymist\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.nature.com\/thescepticalchymist\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.nature.com\/thescepticalchymist\/wp-json\/wp\/v2\/users\/541"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.nature.com\/thescepticalchymist\/wp-json\/wp\/v2\/comments?post=5815"}],"version-history":[{"count":0,"href":"https:\/\/blogs.nature.com\/thescepticalchymist\/wp-json\/wp\/v2\/posts\/5815\/revisions"}],"wp:attachment":[{"href":"https:\/\/blogs.nature.com\/thescepticalchymist\/wp-json\/wp\/v2\/media?parent=5815"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.nature.com\/thescepticalchymist\/wp-json\/wp\/v2\/categories?post=5815"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.nature.com\/thescepticalchymist\/wp-json\/wp\/v2\/tags?post=5815"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}