{"id":1749,"date":"2010-02-21T09:59:57","date_gmt":"2010-02-21T08:59:57","guid":{"rendered":"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=1749"},"modified":"2026-06-17T16:48:55","modified_gmt":"2026-06-17T15:48:55","slug":"the-structure-of-the-hydrogen-ion-in-water","status":"publish","type":"post","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=1749","title":{"rendered":"The structure of the hydrogen ion in water."},"content":{"rendered":"<div class=\"kcite-section\" kcite-section-id=\"1749\">\n<p>Stoyanov, Stoyanova and  Reed recently published on the structure of the hydrogen ion in water. Their model was H(H<sub>2<\/sub>O)<sub>n<\/sub><sup>+<\/sup>,  where n=6<span id=\"cite_ITEM-1749-0\" name=\"citation\"><a href=\"#ITEM-1749-0\">[1]<\/a><\/span> This suggestion was picked up by  Steve Bachrach on his <a href=\"http:\/\/comporgchem.com\/blog\/?p=784\" target=\"_blank\">blog<\/a>, where he added a further three structures to the proposed list, and noted of course that with this type of system there must be a fair chance that the true structure consists of a well-distributed Boltzmann population of a number of almost iso-energetic forms.<\/p>\n<div id=\"attachment_1750\" style=\"width: 258px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/HH2O6.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1750\" class=\"size-full wp-image-1750\" title=\"H(H2O)6\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/HH2O6.jpg\" alt=\"\" width=\"248\" height=\"187\" \/><\/a><p id=\"caption-attachment-1750\" class=\"wp-caption-text\">The proposed structure of the hydrated proton in water<\/p><\/div>\n<p>The evidence for the structure above comes from IR spectra. These operate on a fast enough scale to freeze-out individual forms, and therefore represent  the instantaneous species rather than time averaged environments. <a href=\"http:\/\/comporgchem.com\/blog\/?p=784#comments\" target=\"_blank\">A lively debate<\/a> started on Steve&#8217;s blog, starting with  Steve&#8217;s observation that the original article had reported only experimental results and no theoretical modelling of the proposed structure. It emerged that one way of modelling such species was within a cavity surrounded bv a continuum field modelling the bulk solvent (water in this case), and in particular one must  properly optimize the structure and calculate the force constants within this field. When this is done, one significant difference between a simple gas-phase model of the structure above and its continuum-field structure emerges.  In the former, the  central  O&#8230;H&#8230;O  motif is symmetric (indeed the entire molecule is  C<sub>2<\/sub>-symmetric).  When the solvent field is applied, this unit desymmetrizes, ending up with one short (1.118\u00c5) and one long (1.295\u00c5) bond. I have transferred discussion of this from  Steve&#8217;s blog to this one so that the resulting vibrations of this species can be shown here in animated form (its not possible to post animations in the comment field of a blog).<\/p>\n<p>Firstly, the model. It is a PBE1PBE\/aug-cc-pVTZ  (the DFT method being the same as Steve used in his modelling, the basis set being rather better)  and the continuum field applied was as SCRF(CPCM,solvent=water).  The complete calculation can be inspected at  DOI: <a href=\"http:\/\/hdl.handle.net\/10042\/to-4261\" target=\"_blank\">10042\/to-4261<\/a>. It is also important to remember that the force constants are harmonic. The resulting vibrations with the highest calculated intensities are tabled below.<\/p>\n<table border=\"1\">\n<tbody>\n<tr>\n<th>Obs<\/th>\n<th><sup>1<\/sup>H freq<\/th>\n<th><strong>Intensity<\/strong><\/th>\n<th><sup>2<\/sup>H freq<\/th>\n<\/tr>\n<tr>\n<td>&#8211;<\/td>\n<td>338<\/td>\n<td>481<\/td>\n<td>?<\/td>\n<\/tr>\n<tr>\n<td>654<\/td>\n<td>476<\/td>\n<td>429<\/td>\n<td>438<\/td>\n<\/tr>\n<tr>\n<td>1202<\/td>\n<td>1242<\/td>\n<td>3837<\/td>\n<td>942<\/td>\n<\/tr>\n<tr>\n<td>1746<\/td>\n<td>1749<\/td>\n<td>599<\/td>\n<td>1284<\/td>\n<\/tr>\n<tr>\n<td>2816<\/td>\n<td>3065<\/td>\n<td>2829<\/td>\n<td>2268<\/td>\n<\/tr>\n<tr>\n<td>&#8211;<\/td>\n<td>3127<\/td>\n<td>913<\/td>\n<td>2253<\/td>\n<\/tr>\n<tr>\n<td>3134<\/td>\n<td>3341<\/td>\n<td>2018<\/td>\n<td>2462<\/td>\n<\/tr>\n<tr>\n<td>3134<\/td>\n<td>3347<\/td>\n<td>668<\/td>\n<td>2424<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>One might note that the vibrations in the range  3100-3300 always tend to be over-estimated using theory, in part because of incomplete basis sets, and in part because the harmonic frequencies are always 200 or more  wavenumbers higher than the observed anharmonic values. The match for the mid range vibrations (1746, 1202) seems remarkably good.  Only the low range value  (654) is significantly out, and this may be another anharmonic effect. Added for good measure are the closest matches to each vibration when the system is fully substituted with  deuterium (because of mode mixing, the modes do not always map exactly; thus the mode at  338 appears to have no exact deuteriated analogue).<\/p>\n<p>The displacement vectors are shown below (click on each picture to obtain an animation).<\/p>\n<table border=\"0\">\n<tbody>\n<tr>\n<td>\n<p><div id=\"attachment_1753\" style=\"width: 185px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1753\" class=\"size-full wp-image-1753\" title=\"476\" onclick=\"jmolInitialize('..\/Jmol\/');jmolSetAppletColor('black');jmolApplet([450,450],'load wp-content\/uploads\/2010\/02\/HH2O6.log;frame 26;zoom 5;moveto 4 0 2 0 90 90;vectors on;vectors 4;vectors scale 5.0; color vectors green; vibration 6;animation mode loop;');\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/476.jpg\" alt=\"\" width=\"175\" height=\"136\" \/><p id=\"caption-attachment-1753\" class=\"wp-caption-text\">Normal mode  476 cm-1.<\/p><\/div><\/td>\n<td>\n<p><div id=\"attachment_1754\" style=\"width: 185px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1754\" class=\"size-full wp-image-1754\" title=\"1242\" onclick=\"jmolInitialize('..\/Jmol\/');jmolSetAppletColor('black');jmolApplet([450,450],'load wp-content\/uploads\/2010\/02\/HH2O6.log;frame 33;zoom 5;moveto 4 0 2 0 90 90;vectors on;vectors 4;vectors scale 5.0; color vectors green; vibration 6;animation mode loop;');\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/1242.jpg\" alt=\"\" width=\"175\" height=\"136\" \/><p id=\"caption-attachment-1754\" class=\"wp-caption-text\">Normal mode  1242.<\/p><\/div><\/td>\n<\/tr>\n<tr>\n<td>\n<p><div id=\"attachment_1755\" style=\"width: 185px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1755\" class=\"size-full wp-image-1755\" title=\"1749\" onclick=\"jmolInitialize('..\/Jmol\/');jmolSetAppletColor('black');jmolApplet([450,450],'load wp-content\/uploads\/2010\/02\/HH2O6.log;frame 41;zoom 5;moveto 4 0 2 0 90 90;vectors on;vectors 4;vectors scale 5.0; color vectors green; vibration 6;animation mode loop;');\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/1749.jpg\" alt=\"\" width=\"175\" height=\"136\" \/><p id=\"caption-attachment-1755\" class=\"wp-caption-text\">Normal mode  1749<\/p><\/div><\/td>\n<td>\n<p><div id=\"attachment_1756\" style=\"width: 185px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1756\" class=\"size-full wp-image-1756\" title=\"3065\" onclick=\"jmolInitialize('..\/Jmol\/');jmolSetAppletColor('black');jmolApplet([450,450],'load wp-content\/uploads\/2010\/02\/HH2O6.log;frame 42;zoom 5;moveto 4 0 2 0 90 90;vectors on;vectors 4;vectors scale 5.0; color vectors green; vibration 6;animation mode loop;');\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/3065.jpg\" alt=\"\" width=\"175\" height=\"136\" \/><p id=\"caption-attachment-1756\" class=\"wp-caption-text\">Normal mode  3065<\/p><\/div><\/td>\n<\/tr>\n<tr>\n<td>\n<p><div id=\"attachment_1758\" style=\"width: 185px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1758\" class=\"size-full wp-image-1758\" title=\"3341\" onclick=\"jmolInitialize('..\/Jmol\/');jmolSetAppletColor('black');jmolApplet([450,450],'load wp-content\/uploads\/2010\/02\/HH2O6.log;frame 44;zoom 5;moveto 4 0 2 0 90 90;vectors on;vectors 4;vectors scale 5.0; color vectors green; vibration 6;animation mode loop;');\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/33411.jpg\" alt=\"\" width=\"175\" height=\"136\" \/><p id=\"caption-attachment-1758\" class=\"wp-caption-text\">Normal mode 3341<\/p><\/div><\/td>\n<td>\n<p><div id=\"attachment_1759\" style=\"width: 185px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1759\" class=\"size-full wp-image-1759\" title=\"3347\" onclick=\"jmolInitialize('..\/Jmol\/');jmolSetAppletColor('black');jmolApplet([450,450],'load wp-content\/uploads\/2010\/02\/HH2O6.log;frame 45;zoom 5;moveto 4 0 2 0 90 90;vectors on;vectors 4;vectors scale 5.0; color vectors green; vibration 6;animation mode loop;');\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/3347.jpg\" alt=\"\" width=\"175\" height=\"136\" \/><p id=\"caption-attachment-1759\" class=\"wp-caption-text\">Normal mode 3347<\/p><\/div><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<div id=\"attachment_1774\" style=\"width: 359px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/IR-H.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1774\" class=\"size-full wp-image-1774\" title=\"IR-H\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/IR-H.jpg\" alt=\"\" width=\"349\" height=\"170\" \/><\/a><p id=\"caption-attachment-1774\" class=\"wp-caption-text\">Calculated  IR spectrum for  H(H2O)6 +<\/p><\/div>\n<div id=\"attachment_1775\" style=\"width: 359px\" class=\"wp-caption aligncenter\"><a href=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/IR-D.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1775\" class=\"size-full wp-image-1775\" title=\"IR-D\" src=\"http:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/IR-D.jpg\" alt=\"\" width=\"349\" height=\"170\" \/><\/a><p id=\"caption-attachment-1775\" class=\"wp-caption-text\">Calculated  IR spectrum for  D(D2O)6 +<\/p><\/div>\n<p>The overall conclusion does seem to be that the structure shown above for the solvated proton  does seem to match the observed IR peaks rather well, and that further more accurate modelling of this species might be a worthwhile endeavour.<\/p>\n<h2>References<\/h2>\n    <ol class=\"kcite-bibliography csl-bib-body\"><\/ol>\n\n<\/div> <!-- kcite-section 1749 -->","protected":false},"excerpt":{"rendered":"<p>Stoyanov, Stoyanova and Reed recently published on the structure of the hydrogen ion in water. Their model was H(H2O)n+, where n=6 This suggestion was picked up by Steve Bachrach on his blog, where he added a further three structures to the proposed list, and noted of course that with this type of system there must [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_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":false,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[1,4],"tags":[152,22,2646,2648,20],"ppma_author":[2661],"class_list":["post-1749","post","type-post","status-publish","format-standard","hentry","category-general","category-interesting-chemistry","tag-animation","tag-gas-phase-model","tag-general","tag-interesting-chemistry","tag-steve-bachrach"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.0 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>The structure of the hydrogen ion in water. - 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=1749\" \/>\n<meta property=\"og:locale\" content=\"en_GB\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"The structure of the hydrogen ion in water. - Henry Rzepa&#039;s Blog\" \/>\n<meta property=\"og:description\" content=\"Stoyanov, Stoyanova and Reed recently published on the structure of the hydrogen ion in water. Their model was H(H2O)n+, where n=6 This suggestion was picked up by Steve Bachrach on his blog, where he added a further three structures to the proposed list, and noted of course that with this type of system there must [&hellip;]\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=1749\" \/>\n<meta property=\"og:site_name\" content=\"Henry Rzepa&#039;s Blog\" \/>\n<meta property=\"article:published_time\" content=\"2010-02-21T08:59:57+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-06-17T15:48:55+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2010\/02\/HH2O6.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"992\" \/>\n\t<meta property=\"og:image:height\" content=\"748\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\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=\"5 minutes\" \/>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"The structure of the hydrogen ion in water. - Henry Rzepa&#039;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=1749","og_locale":"en_GB","og_type":"article","og_title":"The structure of the hydrogen ion in water. - Henry Rzepa&#039;s Blog","og_description":"Stoyanov, Stoyanova and Reed recently published on the structure of the hydrogen ion in water. 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Rather than the expected triangular form with three OH---O hydrogen bonds, the lowest energy form only had two such bonds, but it matched the microwave data much better. Here I\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":13033,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=13033","url_meta":{"origin":1749,"position":1},"title":"The solvation of ion pairs.","author":"Henry Rzepa","date":"November 6, 2014","format":false,"excerpt":"Solvolytic mechanisms are amongst the oldest studied, but reproducing their characteristics using computational methods has been a challenging business. This post was inspired by reading Steve Bachrach's post, itself alluding to this aspect in the title \"Computationally handling ion pairs\". It references this recent article on the topic in which\u2026","rel":"","context":"In &quot;reaction mechanism&quot;","block_context":{"text":"reaction mechanism","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=1086"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":18555,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=18555","url_meta":{"origin":1749,"position":2},"title":"Dispersion &#8220;bonds&#8221;: a new example with an ultra-short H&#8230;H distance.","author":"Henry Rzepa","date":"June 26, 2017","format":false,"excerpt":"About 18 months ago, there was much discussion\u00a0on this blog about a system reported by Bob Pascal and co-workers containing a short H...H contact of ~1.5\u00c5. In this system, the hydrogens were both attached to Si as Si-H...H-Si and compressed together by rings. Now a new report and\u00a0commented upon by\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.ic.ac.uk\/rzepa\/blog\/wp-content\/uploads\/2017\/06\/201-1024x987.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":4952,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=4952","url_meta":{"origin":1749,"position":3},"title":"The importance of being complete.","author":"Henry Rzepa","date":"September 26, 2011","format":false,"excerpt":"To (mis)quote Oscar Wilde again, \"\u201cTo lose one methyl group may be regarded as a misfortune; to lose both looks like carelessness.\u201d Here, I refer to the (past) tendency of molecular modellers to simplify molecular structures. Thus in 1977, quantum molecular modelling, even at the semi-empirical level, was beset by\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\/2011\/09\/cbdzw1.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":17279,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=17279","url_meta":{"origin":1749,"position":4},"title":"The dipole moments of highly polar molecules: glycine zwitterion.","author":"Henry Rzepa","date":"December 24, 2016","format":false,"excerpt":"The previous posts produced discussion about the dipole moments of highly polar molecules. Here to produce some reference points for further discussion I look at the dipole moment of glycine, the classic\u00a0zwitterion (an internal ion-pair). Dielectric relaxation studies of glycine-water mixtures yield values that range from\u00a015.7D to 11.9D although these\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\/2016\/12\/051.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":12705,"url":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?p=12705","url_meta":{"origin":1749,"position":5},"title":"The  5\u03c3-confidence level: how much chemistry achieves this?","author":"Henry Rzepa","date":"July 5, 2014","format":false,"excerpt":"I was lucky enough to attend the announcement made in 2012 of the discovery of the Higgs Boson. It consisted of a hour-long talk mostly about statistics, and how the particle physics community can only claim a discovery when their data has\u00a0achieved a 5\u03c3 confidence level. This represents a 1\u2026","rel":"","context":"In &quot;General&quot;","block_context":{"text":"General","link":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/?cat=1"},"img":{"alt_text":"","src":"","width":0,"height":0},"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","author_category":"1","first_name":"Henry","last_name":"Rzepa","user_url":"https:\/\/orcid.org\/0000-0002-8635-8390","job_title":"","description":"Henry Rzepa is Emeritus Professor of Computational Chemistry at Imperial College London."}],"_links":{"self":[{"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1749","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=1749"}],"version-history":[{"count":1,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1749\/revisions"}],"predecessor-version":[{"id":31687,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=\/wp\/v2\/posts\/1749\/revisions\/31687"}],"wp:attachment":[{"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1749"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1749"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1749"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/www.ch.ic.ac.uk\/rzepa\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fppma_author&post=1749"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}