{"id":18277,"date":"2017-05-06T19:23:48","date_gmt":"2017-05-06T18:23:48","guid":{"rendered":"http:\/\/www.ch.imperial.ac.uk\/rzepa\/blog\/?p=18277"},"modified":"2017-05-30T07:36:41","modified_gmt":"2017-05-30T06:36:41","slug":"how-does-carbon-dioxide-coordinate-to-a-metal","status":"publish","type":"post","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18277","title":{"rendered":"How does carbon dioxide coordinate to a metal?"},"content":{"rendered":"<div class=\"kcite-section\" kcite-section-id=\"18277\">\n<p>Mention carbon dioxide (CO<sub>2<\/sub>) to most chemists and its properties as a metal ligand are not the first aspect that springs to mind. Here thought I might take a look at how it might act as such.<\/p>\n<p>There are up to\u00a0five binding modes with one metal that one might envisage:<\/p>\n<ol>\n<li>Bonded\u00a0interaction with the metal <em>via<\/em> just one oxygen atom,<\/li>\n<li>Bonded\u00a0interaction <em>via<\/em> just the central carbon atom,<\/li>\n<li>Bonded\u00a0interaction <em>via<\/em> the\u00a0\u03c0-face of one C=O double bond,<\/li>\n<li>A weaker non-bonded interaction <em>via<\/em> carbon, or<\/li>\n<li><em>via<\/em> oxygen.<\/li>\n<\/ol>\n<p>Search queries of the Cambridge structure database (CSD) for these five modes are illustrated below (dataDOI:\u00a0<a href=\"https:\/\/data.hpc.imperial.ac.uk\/resolve\/?doi=2524&amp;access=\">10.14469\/hpc\/2524<\/a>), with the constraints being applied to how many bonds (of unspecified type) each atom carries, along with no disorder and no errors. Thus query <strong>1<\/strong> is constrained by 1-coordination on one oxygen, and two on the carbon and other oxygen.\u00a0<\/p>\n<p><img decoding=\"async\" class=\"aligncenter size-large wp-image-18282\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/111-368x1024.jpg\" alt=\"\" width=\"200\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/111-368x1024.jpg 368w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/111-108x300.jpg 108w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/111.jpg 454w\" sizes=\"(max-width: 368px) 100vw, 368px\" \/><\/p>\n<ol>\n<li>This query yields four hits:\u00a0<a href=\"https:\/\/dx.doi.org\/10.5517\/ccvcdq9\" target=\"_blank\" rel=\"noopener noreferrer\">10.5517\/ccvcdq9<\/a>, <a href=\"https:\/\/dx.doi.org\/10.5517\/cc12nq6n\" target=\"_blank\" rel=\"noopener noreferrer\">10.5517\/cc12nq6n<\/a>,\u00a0<a href=\"https:\/\/dx.doi.org\/10.5517\/cc12nq5m\" target=\"_blank\" rel=\"noopener noreferrer\">10.5517\/cc12nq5m<\/a>,\u00a0<a href=\"https:\/\/dx.doi.org\/10.5517\/cc12nq4l\" target=\"_blank\" rel=\"noopener noreferrer\">10.5517\/cc12nq4l<\/a>. The angle subtended at the central carbon of the\u00a0CO<sub>2<\/sub>\u00a0ranges from 172-176\u00b0, a very modest bending of the linear CO<sub>2<\/sub>. There are no examples where the metal is bonded to both oxygens.<img decoding=\"async\" class=\"aligncenter size-full wp-image-18285\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/112.jpg\" alt=\"\" width=\"350\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/112.jpg 720w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/112-300x226.jpg 300w\" sizes=\"(max-width: 720px) 100vw, 720px\" \/><\/li>\n<li>The next category involves the metal binding just to the central carbon. Two examples are known, differentiated from O-coordination by a more acute angle at the central carbon of 121-132\u00b0.<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-18290\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/078.jpg\" alt=\"\" width=\"350\" height=\"430\" \/><\/li>\n<li>The\u00a0\u03c0-coordinated type requires a slightly more complex search query, shown below. The \u03c0-complex is defined as adding one coordination to each of one oxygen and the carbon.\u00a0\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-18279\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/109.jpg\" alt=\"\" width=\"450\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/109.jpg 862w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/109-300x239.jpg 300w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/109-768x613.jpg 768w\" sizes=\"(max-width: 862px) 100vw, 862px\" \/><\/p>\n<p>This reveals 16 examples:<br \/>\n <img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-large wp-image-18281\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/110-1024x756.jpg\" alt=\"\" width=\"450\" height=\"332\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/110-1024x756.jpg 1024w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/110-300x221.jpg 300w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/110-768x567.jpg 768w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/110.jpg 1926w\" sizes=\"auto, (max-width: 450px) 100vw, 450px\" \/><\/p>\n<p>The sine of the angle subtended at the centroid of one C-O bond shows that for most of the examples, the metal is\u00a0close to perpendicular to this bond. The angle subtended at the central carbon ranges from 128-138, rather larger than the examples where the metal is bound just to the carbon. I have picked these two for illustration. The first (dataDOI:\u00a0<a href=\"https:\/\/dx.doi.org\/10.5517\/cc86r17\" target=\"_blank\" rel=\"noopener noreferrer\">10.5517\/cc86r17<\/a>) contains both CO<sub>2<\/sub> and CO coordinated to the metal.<img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-18294\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/080.jpg\" alt=\"\" width=\"400\" height=\"216\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/080.jpg 400w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/080-300x162.jpg 300w\" sizes=\"auto, (max-width: 400px) 100vw, 400px\" \/>This one (dataDOI: <a href=\"http:\/\/dx.doi.org\/10.1021\/ic101652e\" target=\"_blank\" rel=\"noopener noreferrer\">10.1021\/ic101652e<\/a>) contains a short metal-centroid distance of 1.78\u00c5 (as also does\u00a0<a href=\"https:\/\/dx.doi.org\/10.5517\/ccz34kr\" target=\"_blank\" rel=\"noopener noreferrer\">10.5517\/ccz34kr<\/a>).\u00a0<br \/>\n <img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-18293\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/079.jpg\" alt=\"\" width=\"359\" height=\"414\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/079.jpg 359w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/079-260x300.jpg 260w\" sizes=\"auto, (max-width: 359px) 100vw, 359px\" \/><\/p>\n<p>There are two examples where\u00a0BOTH\u00a0\u03c0-CO bonds are coordinated to a metal;\u00a0<a href=\"https:\/\/dx.doi.org\/10.5517\/ccqlv7c\" target=\"_blank\" rel=\"noopener noreferrer\">10.5517\/ccqlv7c<\/a>\u00a0and\u00a0<a href=\"https:\/\/dx.doi.org\/10.5517\/ccqlv8d\" target=\"_blank\" rel=\"noopener noreferrer\">10.5517\/ccqlv8d<\/a>\u00a0(Ni-centroid distance 1.9\u00c5) but these are intriguing because the two\u00a0\u03c0-complexes are co-planar and not orthogonal.<br \/>\n <img decoding=\"async\" class=\"aligncenter size-full wp-image-18306\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/083.jpg\" alt=\"\" width=\"400\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/083.jpg 494w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/083-300x287.jpg 300w\" sizes=\"(max-width: 494px) 100vw, 494px\" \/><\/p>\n<\/li>\n<li>The final two cases are defined in the CSD database by having not so much bonds between metal and either C or O, as close intermolecular contacts typical of <em>e.g.<\/em> hydrogen bonds. This one (dataDOI:\u00a0<a href=\"https:\/\/dx.doi.org\/10.5517\/cc12nq9r\" target=\"_blank\" rel=\"noopener noreferrer\">10.5517\/cc12nq9r<\/a>) is to Fe, with a metal-C distance of 2.87\u00c5 which is significantly shorter than the anticipated sum of the van der Waals radii of the two atoms.<img decoding=\"async\" class=\"aligncenter size-full wp-image-18300\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/081.jpg\" alt=\"\" width=\"400\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/081.jpg 711w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/081-300x159.jpg 300w\" sizes=\"(max-width: 711px) 100vw, 711px\" \/> The next (dataDOI:\u00a0<a href=\"https:\/\/dx.doi.org\/10.5517\/cc12npn2\" target=\"_blank\" rel=\"noopener noreferrer\">10.5517\/cc12npn2<\/a>) has a close approach of Co to O of 2.23\u00c5.\u00a0The angles subtended at the carbon range from 174-180\u00b0. There are no convincing examples of close non-bonded approaches of the metal to both oxygen atoms simultaneously.<img decoding=\"async\" class=\"aligncenter size-full wp-image-18301\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/082.jpg\" alt=\"\" width=\"400\" srcset=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/082.jpg 696w, https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/082-300x162.jpg 300w\" sizes=\"(max-width: 696px) 100vw, 696px\" \/><\/li>\n<\/ol>\n<p>It is striking that the searches (as defined above) reveal relatively few examples. This might simply be a result of how\u00a0the compounds are indexed in the CSD, reflected in the coordination constraints applied in the searches. Nevertheless, we see three quite different types of ligand-metal coordination in which bonds can be said to form and a more diffuse spectrum of weaker interactions to carbon dioxide. As a metal ligand, it is certainly interesting! Several deserve their wavefunctions looked at and I might report back on this aspect.<\/p>\n<!-- kcite active, but no citations found -->\n<\/div> <!-- kcite-section 18277 -->","protected":false},"excerpt":{"rendered":"<p>Mention carbon dioxide (CO2) to most chemists and its properties as a metal ligand are not the first aspect that springs to mind. Here thought I might take a look at how it might act as such. There are up to\u00a0five binding modes with one metal that one might envisage: Bonded\u00a0interaction with the metal via [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"activitypub_content_warning":"","activitypub_content_visibility":"","activitypub_max_image_attachments":5,"activitypub_interaction_policy_quote":"anyone","activitypub_status":"","footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[1745],"tags":[1440,2186,289,557,1395,2185,1552,2189,157,2188,2184,1695,734,2187],"ppma_author":[2661],"class_list":["post-18277","post","type-post","status-publish","format-standard","hentry","category-crystal_structure_mining","tag-carbon","tag-carbon-capture-storage","tag-carbon-dioxide","tag-chemical-bonding","tag-chemistry","tag-environment","tag-ligand","tag-ligand-metal-coordination","tag-metal","tag-metal-ligand","tag-propellants","tag-search-queries","tag-search-query","tag-short-metal-centroid-distance"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.5 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>How does carbon dioxide coordinate to a metal? - Henry Rzepa&#039;s Blog<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18277\" \/>\n<meta property=\"og:locale\" content=\"en_GB\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"How does carbon dioxide coordinate to a metal? - Henry Rzepa&#039;s Blog\" \/>\n<meta property=\"og:description\" content=\"Mention carbon dioxide (CO2) to most chemists and its properties as a metal ligand are not the first aspect that springs to mind. 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There are up to\u00a0five binding modes with one metal that one might envisage: Bonded\u00a0interaction with the metal via [&hellip;]","og_url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18277","og_site_name":"Henry Rzepa&#039;s Blog","article_published_time":"2017-05-06T18:23:48+00:00","article_modified_time":"2017-05-30T06:36:41+00:00","og_image":[{"url":"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/111-368x1024.jpg","type":"","width":"","height":""}],"author":"Henry Rzepa","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Henry Rzepa","Estimated reading time":"3 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18277#article","isPartOf":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18277"},"author":{"name":"Henry Rzepa","@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/#\/schema\/person\/2b40f7b9c872a4dc1547e040a11b6281"},"headline":"How does carbon dioxide coordinate to a metal?","datePublished":"2017-05-06T18:23:48+00:00","dateModified":"2017-05-30T06:36:41+00:00","mainEntityOfPage":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18277"},"wordCount":578,"commentCount":2,"image":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18277#primaryimage"},"thumbnailUrl":"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/05\/111-368x1024.jpg","keywords":["Carbon","Carbon Capture &amp; Storage","carbon dioxide","chemical bonding","Chemistry","Environment","Ligand","ligand-metal coordination","metal","metal ligand","Propellants","Search queries","search query","short metal-centroid distance"],"articleSection":["crystal_structure_mining"],"inLanguage":"en-GB","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18277#respond"]}]},{"@type":"WebPage","@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18277","url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18277","name":"How does carbon dioxide coordinate to a metal? 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I had previously mooted that the Fe\u2a78C combination might be\u2026","rel":"","context":"In &quot;crystal_structure_mining&quot;","block_context":{"text":"crystal_structure_mining","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=1745"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/05\/Screenshot-703-1024x818.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":23588,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=23588","url_meta":{"origin":18277,"position":1},"title":"Two new reality-based suggestions for molecules with a metal M\u2a78C quadruple bond.","author":"Henry Rzepa","date":"May 8, 2021","format":false,"excerpt":"Following from much discussion over the last decade about the nature of C2, a diatomic molecule which some have suggested sustains a quadruple bond between the two carbon atoms, new ideas are now appearing for molecules in which such a bond may also exist between carbon and a transition metal\u2026","rel":"","context":"In &quot;crystal_structure_mining&quot;","block_context":{"text":"crystal_structure_mining","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=1745"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/05\/Screenshot-702-300x63.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":8048,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=8048","url_meta":{"origin":18277,"position":2},"title":"Trimethylenemethane Ruthenium benzene","author":"Henry Rzepa","date":"October 17, 2012","format":false,"excerpt":"Every once in a while, one encounters a molecule which instantly makes an interesting point. Thus Ruthenium is ten electrons short of completing an 18-electron shell, and it can form a complex with benzene on one face and a ligand known as trimethylenemethane on the other. This four-carbon molecule has\u2026","rel":"","context":"In &quot;Interesting chemistry&quot;","block_context":{"text":"Interesting chemistry","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=4"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.ch.imperial.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2012\/10\/JODLIX.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":30548,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548","url_meta":{"origin":18277,"position":3},"title":"Molecules of the year 2025: Benzene-busting inverted sandwich.","author":"Henry Rzepa","date":"January 1, 2026","format":false,"excerpt":"Sandwich compounds are the colloquial term used for molecules where a metal atom such as an iron dication is \"sandwiched\" between two carbon-based rings as ligands, most commonly cyclopentadienyl anion (the \"bread\") as in e.g. Ferrocene - a molecule first discovered in 1951. An \"inverted\" sandwich is where the carbon\u2026","rel":"","context":"In &quot;Interesting chemistry&quot;","block_context":{"text":"Interesting chemistry","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=4"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":10733,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=10733","url_meta":{"origin":18277,"position":4},"title":"Is dicarbon (C2) a molecule of chemical interest?","author":"Henry Rzepa","date":"July 3, 2013","format":false,"excerpt":"C2\u00a0(dicarbon) is certainly interesting from a theoretical point of view. Whether or not it can be described as having a quadruple bond has induced much passionate discussion,,,. Its occurrence in space and in flames is also well-known. But does it have what might be called a conventional chemistry? Other highly\u2026","rel":"","context":"In &quot;Interesting chemistry&quot;","block_context":{"text":"Interesting chemistry","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=4"},"img":{"alt_text":"Click for  3D","src":"https:\/\/i0.wp.com\/www.ch.imperial.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2013\/07\/LaOsC1.jpeg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":21883,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=21883","url_meta":{"origin":18277,"position":5},"title":"Molecules of the year 2019: Hexagonal planar crystal structures.","author":"Henry Rzepa","date":"January 23, 2020","format":false,"excerpt":"Here is another selection from the Molecules-of-the-Year shortlist published by C&E News, in which hexagonal planar transition metal coordination is identified. This was a mode of metal coordination first mooted more than 100 years ago, but with the first examples only being discovered recently.\u00a0The C&E News example comprises a central\u2026","rel":"","context":"In &quot;crystal_structure_mining&quot;","block_context":{"text":"crystal_structure_mining","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=1745"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2020\/01\/norloy-300x263.jpg?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]}],"jetpack_likes_enabled":false,"authors":[{"term_id":2661,"user_id":1,"is_guest":0,"slug":"admin","display_name":"Henry Rzepa","avatar_url":"https:\/\/secure.gravatar.com\/avatar\/897b6740f7f599bca7942cdf7d7914af5988937ae0e3869ab09aebb87f26a731?s=96&d=blank&r=g","0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""}],"_links":{"self":[{"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/posts\/18277","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=18277"}],"version-history":[{"count":24,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/posts\/18277\/revisions"}],"predecessor-version":[{"id":18314,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/posts\/18277\/revisions\/18314"}],"wp:attachment":[{"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=18277"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=18277"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=18277"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fppma_author&post=18277"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}