{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T12:53:17Z","timestamp":1792068797998,"version":"4.4.0"},"reference-count":25,"publisher":"American Chemical Society (ACS)","issue":"41","license":[{"start":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T00:00:00Z","timestamp":1790640000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"name":"JSPS KAKENHI"},{"name":"NIMS Cooperative Research Promotion Program from the National Institute for Materials Science Cooperative Promotion"},{"name":"Japanese Synchrotron Radiation Research Institute"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,15]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>This study aimed to elucidate the structural evolution of supercritical fluid hydrogen (SCF H2) under high pressure. X-ray diffraction was performed on SCF H2 using synchrotron radiation at room temperature. The structure factor S(Q) was observed in a low-Q region at each pressure, revealing a crossover at around 0.56 GPa, consistent with our previous Raman spectroscopy results. The average volume per molecule was calculated at each pressure using the center-to-center distance between the nearest neighboring H2 molecules, reflecting van der Waals interactions and compression of the internuclear distance. The volumes calculated from the face-centered cubic model were consistent with those derived from the cited equation of state, with a slight discrepancy that increased gradually with the pressure. This finding indicates that further densification following the crossover occurs primarily by intra-atomic\/molecular mechanisms rather than intermolecular shortening of distances, which cannot be adequately explained by the close-packed coordination model alone.<\/jats:p>","DOI":"10.1021\/acs.jpclett.6c02439","type":"journal-article","created":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T01:02:08Z","timestamp":1790730128000},"page":"11754-11759","source":"Crossref","is-referenced-by-count":0,"title":["A High-Density\nSupercritical Fluid of H2"],"prefix":"10.1021","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-0016-3750","authenticated-orcid":true,"given":"Atsuko","family":"Nakayama","sequence":"first","affiliation":[{"name":"Iwate University , , 4-3-5 Ueda , , ,","place":["Morioka, Iwate, Japan, 020-8551"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naoto","family":"Fujii","sequence":"additional","affiliation":[{"name":"Iwate University , , 4-3-5 Ueda , , ,","place":["Morioka, Iwate, Japan, 020-8551"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Koji","family":"Hirama","sequence":"additional","affiliation":[{"name":"Iwate University , , 4-3-5 Ueda , , ,","place":["Morioka, Iwate, Japan, 020-8551"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kentaro","family":"Hamada","sequence":"additional","affiliation":[{"name":"Iwate University , , 4-3-5 Ueda , , ,","place":["Morioka, Iwate, Japan, 020-8551"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0560-8325","authenticated-orcid":true,"given":"Katsuya","family":"Shimizu","sequence":"additional","affiliation":[{"name":"The University of Osaka , , Machikaneyama 1-3 , , ,","place":["Toyonaka, Osaka, Japan, 560-8531"]},{"name":"Ehime University , , 2-5 Bunkyo-Cho , , ,","place":["Matsuyama, Ehime, Japan, 790-8577"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuki","family":"Nakamoto","sequence":"additional","affiliation":[{"name":"The University of Osaka , , Machikaneyama 1-3 , , ,","place":["Toyonaka, Osaka, Japan, 560-8531"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7010-9867","authenticated-orcid":true,"given":"Satoshi","family":"Nakano","sequence":"additional","affiliation":[{"name":"National Institute for Materials Science (NIMS) , Namiki 1-1 , , ,","place":["Tsukuba, Ibaraki, Japan, 305-0044"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saori","family":"Kawaguchi-Imada","sequence":"additional","affiliation":[{"name":"Japan Synchrotron Radiation Research Institute , , 1-1-1 Kouto, Sayo-cho, Sayo-gun , ,","place":["Hyogo, Japan, 679-5198"]},{"name":"Kyoto University , , 1-1-1 Kouto, Sayo-cho, Sayo-gun , ,","place":["Hyogo, Japan, 679-5198"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2736-9855","authenticated-orcid":true,"given":"Yuichi","family":"Akahama","sequence":"additional","affiliation":[{"name":"University of Hyogo , , 3-2-1 Kamigohri , ,","place":["Hyogo, Japan, 678-1297"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayako","family":"Ohmura","sequence":"additional","affiliation":[{"name":"Niigata University , , 8050 Ikarashi 2-no-cho, Nishi-ku , ,","place":["Niigata, Japan, 950-2181"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2026,9,29]]},"reference":[{"issue":"7","key":"2026101508210974100_cit1","doi-asserted-by":"publisher","DOI":"10.1063\/1.3076123","article-title":"Inelastic x-ray scattering from high\npressure fluids in a diamond anvil cell","volume":"94","author":"Gorelli","year":"2009","journal-title":"Appl.\nPhys. 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