{"id":30548,"date":"2026-01-01T10:10:47","date_gmt":"2026-01-01T10:10:47","guid":{"rendered":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548"},"modified":"2026-01-01T10:12:23","modified_gmt":"2026-01-01T10:12:23","slug":"molecules-of-the-year-2025-benzene-busting-inverted-sandwich","status":"publish","type":"post","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548","title":{"rendered":"Molecules of the year 2025: Benzene-busting inverted sandwich."},"content":{"rendered":"
\n

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> – a molecule first discovered in 1951. An “inverted” sandwich is where the carbon ring is itself sandwiched between two metal ions and one such was reported this year [1]<\/a><\/span> containing benzene in the middle with scandium as the metal. The novelty of the subsequent four-electron reduction of the benzene “filler” and its ring opening to a linear hexadiene unit resulted in this being selected as one “molecule of the year<\/a>” for 2025.<\/p>\n

The first example of such an inverted sandwich was reported in 1983 (CAMZAP\u2021<\/sup>)[2]<\/a><\/span> and this made me wonder how many examples have subsequently been discovered. A search of the CSD (crystal structure database) using the following query was undertaken.<\/p>\n

\"\"<\/p>\n

This query places a centroid to the central benzene ring and measures its distances to the two metal ions, along with the angle subtended at the centroid. A C-C distance is also defined. The results (82 hits, increasing to 182 for the more general CR, R=C or H above) are shown below (Figure 1).<\/p>\n

\"\"<\/p>\n

Figure 1a. Metal to centroid distances and angle at the benzene centroid.<\/p>\n

\"\"<\/p>\n

Figure 1b.\u00a0Benzene CC ring distances.<\/p>\n

\"\"<\/p>\n

Figure 1c.\u00a0Publication year for benzene as sandwich filler.<\/p>\n

\"\"<\/p>\n

Figure 1d. Publication year for structures including substituted benzenes as sandwich filler.<\/p>\n

An outlier in Figure 1c that dates from 1975 also corresponds to the outlier in Figure 1a seen as a blue dot and is actually an example of TWO metal Pd atoms sandwiched by benzene rings (inadvertently captured by the search definition above). There has been an explosive growth in the reports of crystal structures of such complexes since 2024, which suggests that this is currently an area of intense activity.<\/p>\n

The molecule of the year referred to above goes by the CSD name BAFHUQ[3]<\/a><\/span> and its structure is shown below (Figure 2, M-centroid length 1.856\u00c5). This molecule has a calculated[4]<\/a><\/span> (D4) dispersion stabilisation of 62.8 kcal\/mol, deriving in large measure from interactions of the isopropyl groups on the P ligand.
\n\"\"<\/p>\n

Figure 2. BAFHUG<\/p>\n

HOQNEK[5]<\/a><\/span>,[6]<\/a><\/span> with Ti as metal (Figure 3) is an example having the shortest M-benzene centroid length (1.69\u00c5). The dispersion contribution in this case is 46.2 kcal\/mol.
\n\"\"
\nFigure 3. HOQNEK<\/p>\n

CALNIP[7]<\/a><\/span>,[8]<\/a><\/span> has the shortest distance to the ring centroid of 1.56\u00c5, with toluene as the sandwich filler.
\n\"\"<\/p>\n

Figure 4. CALNIP (Fe-centroid 1.56\u00c5, K-centroid 2.96\u00c5).<\/p>\n

The trends above suggest that a new area of the reactivity of aromatic molecules such as benzene when sandwiched between two metal atoms may be emerging.<\/p>\n

\n

\u2021<\/sup>Actually a “triple decker” sandwich containing both ligand-metal-ligand and the inverted metal-ligand-metal motifs.<\/p>\n

References<\/h2>\n
  1. L. Zhang, Z. Jiang, C. Zhang, K. Cheng, S. Li, Y. Gao, X. Wang, and J. Chu, \"Room Temperature Ring Opening of Benzene by Four-Electron Reduction and Carbonylation\", Journal of the American Chemical Society<\/i>, vol. 147, pp. 25017-25023, 2025. https:\/\/doi.org\/10.1021\/jacs.5c08414<\/a>\n\n<\/li>\n
  2. A.W. Duff, K. Jonas, R. Goddard, H.J. Kraus, and C. Krueger, \"The first triple-decker sandwich with a bridging benzene ring\", Journal of the American Chemical Society<\/i>, vol. 105, pp. 5479-5480, 1983. https:\/\/doi.org\/10.1021\/ja00354a050<\/a>\n\n<\/li>\n
  3. Zhang, Leiyang., Jiang, Ziang., Zhang, Cuijuan., Cheng, Kehang., Li, Songyang., Gao, Yueze., Wang, Xiaotai., and Chu, Jiaxiang., \"CCDC 2417331: Experimental Crystal Structure Determination\", 2025. https:\/\/doi.org\/10.5517\/ccdc.csd.cc2m4ffn<\/a>\n\n<\/li>\n
  4. H. Rzepa, \"Molecules of the year 2025: Benzene-busting inverted sandwich.\", 2025. https:\/\/doi.org\/10.14469\/hpc\/15647<\/a>\n\n<\/li>\n
  5. E. \u00c1lvarez-Ruiz, I. Sancho, M. Navarro, I. Fern\u00e1ndez, C. Santamar\u00eda, and A. Hern\u00e1n-G\u00f3mez, \"A Mixed-Valence Ti(II)\/Ti(III) Inverted Sandwich Compound as a Regioselective Catalyst for the Uncommon 1,3,5-Alkyne Cyclotrimerization\", Inorganic Chemistry<\/i>, vol. 63, pp. 8642-8653, 2024. https:\/\/doi.org\/10.1021\/acs.inorgchem.4c00149<\/a>\n\n<\/li>\n
  6. A\u0301lvarez-Ruiz, Elena., Sancho, Ignacio., Navarro, Marta., Ferna\u0301ndez, Israel., Santamari\u0301a, Cristina., and Herna\u0301n-Go\u0301mez, Alberto., \"CCDC 2324418: Experimental Crystal Structure Determination\", 2024. https:\/\/doi.org\/10.5517\/ccdc.csd.cc2j0r7k<\/a>\n\n<\/li>\n
  7. A.A. Danopoulos, P. Braunstein, K.Y. Monakhov, J. van Leusen, P. K\u00f6gerler, M. Cl\u00e9mancey, J. Latour, A. Benayad, M. Tromp, E. Rezabal, and G. Frison, \"Heteroleptic, two-coordinate [M(NHC){N(SiMe<sub>3<\/sub>)<sub>2<\/sub>}] (M = Co, Fe) complexes: synthesis, reactivity and magnetism rationalized by an unexpected metal oxidation state\", Dalton Transactions<\/i>, vol. 46, pp. 1163-1171, 2017. https:\/\/doi.org\/10.1039\/c6dt03565e<\/a>\n\n<\/li>\n
  8. Danopoulos, Andreas A.., Braunstein, Pierre., Monakhov, Kirill Yu.., van Leusen, Jan., K\u00f6gerler, Paul., Cl\u00e9mancey, Martin., Latour, Jean-Marc., Benayad, Anass., Tromp, Moniek., Rezabal, Elixabete., and Frison, Gilles., \"CCDC 1469268: Experimental Crystal Structure Determination\", 2017. https:\/\/doi.org\/10.5517\/ccdc.csd.cc1l9wrj<\/a>\n\n<\/li>\n<\/ol>\n\n<\/div> ","protected":false},"excerpt":{"rendered":"

    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 ring is itself sandwiched between […]<\/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":"federated","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":[4],"tags":[],"ppma_author":[2661],"class_list":["post-30548","post","type-post","status-publish","format-standard","hentry","category-interesting-chemistry"],"yoast_head":"\nMolecules of the year 2025: Benzene-busting inverted sandwich. - Henry Rzepa'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=30548\" \/>\n<meta property=\"og:locale\" content=\"en_GB\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Molecules of the year 2025: Benzene-busting inverted sandwich. - Henry Rzepa's Blog\" \/>\n<meta property=\"og:description\" content=\"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 ring is itself sandwiched between […]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548\" \/>\n<meta property=\"og:site_name\" content=\"Henry Rzepa's Blog\" \/>\n<meta property=\"article:published_time\" content=\"2026-01-01T10:10:47+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-01-01T10:12:23+00:00\" \/>\n<meta name=\"author\" content=\"Henry Rzepa\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Henry Rzepa\" \/>\n\t<meta name=\"twitter:label2\" content=\"Estimated reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"4 minutes\" \/>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"Molecules of the year 2025: Benzene-busting inverted sandwich. - Henry Rzepa's Blog","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548","og_locale":"en_GB","og_type":"article","og_title":"Molecules of the year 2025: Benzene-busting inverted sandwich. - Henry Rzepa's Blog","og_description":"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 ring is itself sandwiched between […]","og_url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548","og_site_name":"Henry Rzepa's Blog","article_published_time":"2026-01-01T10:10:47+00:00","article_modified_time":"2026-01-01T10:12:23+00:00","author":"Henry Rzepa","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Henry Rzepa","Estimated reading time":"4 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548#article","isPartOf":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548"},"author":{"name":"Henry Rzepa","@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/#\/schema\/person\/2b40f7b9c872a4dc1547e040a11b6281"},"headline":"Molecules of the year 2025: Benzene-busting inverted sandwich.","datePublished":"2026-01-01T10:10:47+00:00","dateModified":"2026-01-01T10:12:23+00:00","mainEntityOfPage":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548"},"wordCount":490,"commentCount":0,"image":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548#primaryimage"},"thumbnailUrl":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2025\/12\/quewry.jpg","articleSection":["Interesting chemistry"],"inLanguage":"en-GB","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548#respond"]}]},{"@type":"WebPage","@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548","url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548","name":"Molecules of the year 2025: Benzene-busting inverted sandwich. - Henry Rzepa's Blog","isPartOf":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/#website"},"primaryImageOfPage":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548#primaryimage"},"image":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548#primaryimage"},"thumbnailUrl":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2025\/12\/quewry.jpg","datePublished":"2026-01-01T10:10:47+00:00","dateModified":"2026-01-01T10:12:23+00:00","author":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/#\/schema\/person\/2b40f7b9c872a4dc1547e040a11b6281"},"breadcrumb":{"@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548#breadcrumb"},"inLanguage":"en-GB","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548"]}]},{"@type":"ImageObject","inLanguage":"en-GB","@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548#primaryimage","url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2025\/12\/quewry.jpg","contentUrl":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2025\/12\/quewry.jpg","width":900,"height":682},{"@type":"BreadcrumbList","@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=30548#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog"},{"@type":"ListItem","position":2,"name":"Molecules of the year 2025: Benzene-busting inverted sandwich."}]},{"@type":"WebSite","@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/#website","url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/","name":"Henry Rzepa's Blog","description":"Chemistry with a twist","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-GB"},{"@type":"Person","@id":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/#\/schema\/person\/2b40f7b9c872a4dc1547e040a11b6281","name":"Henry Rzepa","image":{"@type":"ImageObject","inLanguage":"en-GB","@id":"https:\/\/secure.gravatar.com\/avatar\/897b6740f7f599bca7942cdf7d7914af5988937ae0e3869ab09aebb87f26a731?s=96&d=blank&r=g370be3a7397865e4fd161aefeb0a5a85","url":"https:\/\/secure.gravatar.com\/avatar\/897b6740f7f599bca7942cdf7d7914af5988937ae0e3869ab09aebb87f26a731?s=96&d=blank&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/897b6740f7f599bca7942cdf7d7914af5988937ae0e3869ab09aebb87f26a731?s=96&d=blank&r=g","caption":"Henry Rzepa"},"description":"Henry Rzepa is Emeritus Professor of Computational Chemistry at Imperial College London.","sameAs":["https:\/\/orcid.org\/0000-0002-8635-8390"],"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?author=1"}]}},"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/pDef7-7WI","jetpack-related-posts":[{"id":8048,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=8048","url_meta":{"origin":30548,"position":0},"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 "Interesting chemistry"","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":2046,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=2046","url_meta":{"origin":30548,"position":1},"title":"Chemistry with a super-twist: A molecular trefoil knot, part 1.","author":"Henry Rzepa","date":"May 31, 2010","format":false,"excerpt":"Something important happened in chemistry for the first time about 100 years ago. A molecule was built (nowadays we would say synthesized) specifically for the purpose of investigating a theory. It was cyclo-octatetraene or (CH)8, and it was made by Willst\u00e4tter and Waser to try to find out if benzene,\u2026","rel":"","context":"In "Interesting chemistry"","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.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/05\/metallatrefoil.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":275,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=275","url_meta":{"origin":30548,"position":2},"title":"A molecule with an identity crisis: Aromatic or anti-aromatic?","author":"Henry Rzepa","date":"April 13, 2009","format":false,"excerpt":"In 1988, Wilke reported molecule 1 It was a highly unexpected outcome of a nickel-catalyzed reaction and was described as a 24-annulene with an unusual 3D shape. Little attention has been paid to this molecule since its original report, but the focus has now returned! The reason is that a\u2026","rel":"","context":"In "Interesting chemistry"","block_context":{"text":"Interesting chemistry","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=4"},"img":{"alt_text":"A [24] annulene. Click on image for model.","src":"https:\/\/i0.wp.com\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2009\/04\/gaytab.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":21407,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=21407","url_meta":{"origin":30548,"position":3},"title":"Does Kekulene have Kekul\u00e9 vibrational modes? Yes!","author":"Henry Rzepa","date":"October 19, 2019","format":false,"excerpt":"Increasingly, individual small molecules are having their structures imaged using STM, including cyclo[18]carbon that I recently discussed. The latest one receiving such treatment is Kekulene. As with cyclo[18]carbon, the point of interest was which of the two resonance structures shown below most closely resembled the measured structure. The one on\u2026","rel":"","context":"In "Interesting chemistry"","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.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2019\/10\/b3-1423-B2u-1024x575.gif?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":9778,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=9778","url_meta":{"origin":30548,"position":4},"title":"Lithiation of heteroaromatic rings: analogy to electrophilic substitution?","author":"Henry Rzepa","date":"March 16, 2013","format":false,"excerpt":"Functionalisation of a (hetero)aromatic ring by selectively (directedly) removing protons using the metal lithium is a relative mechanistic newcomer, compared to the pantheon of knowledge on\u00a0aromatic electrophilic substitution. Investigating the mechanism using quantum calculations poses some interesting challenges, ones I have not previously discussed on this blog. My model will\u2026","rel":"","context":"In "Hypervalency"","block_context":{"text":"Hypervalency","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=7"},"img":{"alt_text":"SUHBEC. CLICK FOR 3D.","src":"https:\/\/i0.wp.com\/www.ch.imperial.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2013\/03\/SUHBEC.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":24503,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=24503","url_meta":{"origin":30548,"position":5},"title":"Molecule of the year 2021: Infinitene.","author":"Henry Rzepa","date":"December 16, 2021","format":false,"excerpt":"The annual \"molecule of the year\" results for 2021 are now available ... and the winner is Infinitene., This is a benzocirculene in the form of a figure eight loop (the infinity symbol), a shape which is also called a lemniscate after the mathematical (2D) function due to Bernoulli. The\u2026","rel":"","context":"In "Chiroptics"","block_context":{"text":"Chiroptics","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=2644"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2021\/12\/infinitene.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\/30548","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=30548"}],"version-history":[{"count":32,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/posts\/30548\/revisions"}],"predecessor-version":[{"id":30682,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/posts\/30548\/revisions\/30682"}],"wp:attachment":[{"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=30548"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=30548"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=30548"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fppma_author&post=30548"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}