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<journal-id journal-id-type="publisher-id">Front. Chem.</journal-id>
<journal-title>Frontiers in Chemistry</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Chem.</abbrev-journal-title>
<issn pub-type="epub">2296-2646</issn>
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<article-id pub-id-type="publisher-id">1428895</article-id>
<article-id pub-id-type="doi">10.3389/fchem.2024.1428895</article-id>
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<subject>Chemistry</subject>
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<subject>Editorial</subject>
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<title-group>
<article-title>Editorial: Syntheses under extreme conditions</article-title>
<alt-title alt-title-type="left-running-head">Bruns et al.</alt-title>
<alt-title alt-title-type="right-running-head">
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fchem.2024.1428895">10.3389/fchem.2024.1428895</ext-link>
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<surname>Bruns</surname>
<given-names>J&#xf6;rn</given-names>
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<xref ref-type="aff" rid="aff1">
<sup>1</sup>
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<xref ref-type="corresp" rid="c001">&#x2a;</xref>
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<name>
<surname>Bykov</surname>
<given-names>Maxim</given-names>
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<xref ref-type="aff" rid="aff2">
<sup>2</sup>
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<name>
<surname>Heymann</surname>
<given-names>Gunter</given-names>
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<xref ref-type="aff" rid="aff3">
<sup>3</sup>
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<contrib contrib-type="author" corresp="yes">
<name>
<surname>Thiele</surname>
<given-names>G&#xfc;nther</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
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<xref ref-type="aff" rid="aff5">
<sup>5</sup>
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<xref ref-type="corresp" rid="c001">&#x2a;</xref>
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<aff id="aff1">
<sup>1</sup>
<institution>Institute of Inorganic Chemistry</institution>, <institution>University of Cologne</institution>, <addr-line>Cologne</addr-line>, <country>Germany</country>
</aff>
<aff id="aff2">
<sup>2</sup>
<institution>Institute of Inorganic and Analytical Chemistry</institution>, <institution>Goethe-University Frankfurt am Main</institution>, <addr-line>Frankfurt</addr-line>, <country>Germany</country>
</aff>
<aff id="aff3">
<sup>3</sup>
<institution>Department of General</institution>, <institution>Inorganic and Theoretical Chemistry</institution>, <institution>Universit&#xe4;t Innsbruck</institution>, <addr-line>Innsbruck</addr-line>, <country>Austria</country>
</aff>
<aff id="aff4">
<sup>4</sup>
<institution>Fachbereich Biologie</institution>, <institution>Chemie und Pharmazie</institution>, <institution>Freie Universit&#xe4;t Berlin</institution>, <addr-line>Berlin</addr-line>, <country>Germany</country>
</aff>
<aff id="aff5">
<sup>5</sup>
<institution>Institut f&#x00FC;r Anorganische und Analytische Chemie, Albert-Ludwigs-Universit&#x00E4;t Freiburg</institution>, <addr-line>Freiburg</addr-line>, <country>Germany</country>
</aff>
<author-notes>
<fn fn-type="edited-by">
<p>
<bold>Edited and reviewed by:</bold> <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/936888/overview">Elena Vladimirovna Boldyreva</ext-link>, Novosibirsk State University, Russia</p>
</fn>
<corresp id="c001">&#x2a;Correspondence: J&#xf6;rn Bruns, <email>j.bruns@uni-koeln.de</email>; Maxim Bykov, <email>maxim.bykov@chemie.uni-frankfurt.de</email>; Gunter Heymann, <email>gunter.heymann@uibk.ac.at</email>; G&#xfc;nther Thiele, <email>guenther.thiele@fu-berlin.de</email>
</corresp>
</author-notes>
<pub-date pub-type="epub">
<day>31</day>
<month>05</month>
<year>2024</year>
</pub-date>
<pub-date pub-type="collection">
<year>2024</year>
</pub-date>
<volume>12</volume>
<elocation-id>1428895</elocation-id>
<history>
<date date-type="received">
<day>07</day>
<month>05</month>
<year>2024</year>
</date>
<date date-type="accepted">
<day>10</day>
<month>05</month>
<year>2024</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#xa9; 2024 Bruns, Bykov, Heymann and Thiele.</copyright-statement>
<copyright-year>2024</copyright-year>
<copyright-holder>Bruns, Bykov, Heymann and Thiele</copyright-holder>
<license xlink:href="http://creativecommons.org/licenses/by/4.0/">
<p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</p>
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<related-article id="RA1" related-article-type="commentary-article" journal-id="Front. Chem." xlink:href="https://www.frontiersin.org/researchtopic/50607" ext-link-type="uri">Editorial on the Research Topic <article-title>Syntheses under extreme conditions</article-title>
</related-article>
<kwd-group>
<kwd>chemistry</kwd>
<kwd>extreme synthesis</kwd>
<kwd>high-pressure</kwd>
<kwd>diamond anvil cell</kwd>
<kwd>inorganic synthesis</kwd>
</kwd-group>
<custom-meta-wrap>
<custom-meta>
<meta-name>section-at-acceptance</meta-name>
<meta-value>Solid State Chemistry</meta-value>
</custom-meta>
</custom-meta-wrap>
</article-meta>
</front>
<body>
<p>&#x201c;Extreme conditions&#x201d; in chemistry greatly depend on the perspective. High temperatures, as commonly used in solid state chemistry may appear &#x201c;extreme&#x201d; to many chemists in other research areas, while a successful synthesis at room temperature of products previously only obtained at very high temperatures, might also be considered &#x201c;extreme&#x201d;. This Research Topic is dedicated to synthesis conditions that are beyond of what is typically feasible with standard laboratory techniques. It emphasizes the fundamental necessity of developing novel methods, training students in these techniques, and a curiosity-driven exploration of &#x201c;How far can we go?&#x201d; These approaches open novel pathways to previously unknown compounds and/or modifications, ultimately expanding our profound understanding of matter.</p>
<p>Undoubtedly, high-pressure syntheses are considered &#x201c;extreme&#x201d; by most chemists, and were employed in the articles of this Research Topic. To synthesize Dy<sub>36</sub>O<sub>11</sub>F<sub>50</sub> [AsO<sub>3</sub>]<sub>12</sub>&#xb7;H<sub>2</sub>O <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fchem.2024.1354690">Schleid et al.</ext-link> followed an approach using suitable binary precursors in water at high-pressure conditions in gold ampoules. The structure comprises seven- and eightfold heteroleptic coordinated Dy<sup>3&#x2b;</sup> species, alongside [AsO<sub>3</sub>]<sup>3&#x2212;</sup> anions and crystal water trapped in large cavities.</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fchem.2023.1306495">Pe&#xf1;a-Alvarez et al.</ext-link> report on the formation of sodium trihydride NaH<sub>3</sub> from the reaction of NaH at high hydrogen pressures of about 30, 40, 50, and 75&#xa0;GPa in a diamond anvil cell. The findings are supported by Raman experiments and are compared to first principle calculations.</p>
<p>NdRe<sub>2</sub> was obtained by Hussein, <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fchem.2024.1259032">Chuvashova et al.</ext-link> in the cubic MgCu<sub>2</sub> structure type from reactions at high-pressure high-temperature conditions in a diamond anvil cell. The results illustrate the formation of Laves phase structures at such special conditions, and the authors discuss connections to nuclear waste materials.</p>
<p>Via a high-pressure high-temperature reaction within a diamond anvil cell, the novel lanthanum hydroxyborate La<sub>2</sub>B<sub>2</sub>O<sub>5</sub>(OH)<sub>2</sub> was obtained. The structure comprises discrete [BO<sub>3</sub>]-units and three crystallographically independent lanthanum positions: one in ninefold, one in tenfold and one in twelvefold coordination, respectively. Besides the synthesis and the crystal structure, the authors Ibragimova, <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fchem.2023.1259000">Chuvashova et al.</ext-link> estimated the band gap by <italic>ab initio</italic> calculations at different pressure points and discuss a possible use as a deep-ultraviolet birefringent material.</p>
<p>Two perovskite related silicates, Fe<sub>0.5</sub>Mg<sub>0.5</sub>Al<sub>0.5</sub>Si<sub>0.5</sub>O<sub>3</sub> and FeMg<sub>0.5</sub>Si<sub>0.5</sub>O<sub>3</sub> are reported by <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fchem.2023.1258389">Koemets et al.</ext-link>, which belong to the bridgmanite mineral class, comprising the most abundant minerals in the Earth&#x2019;s lower mantle. The authors observed a spin transition for Fe<sup>3&#x2b;</sup> in the iron rich phase at pressures higher than 40&#xa0;GPa.</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fchem.2023.1257942">Glazyrin et al.</ext-link> report on the synthesis of orthorhombic BiN (space group <italic>Pbcn</italic>) from the reaction of the two pnictogens bismuth and nitrogen at pressures above 40&#xa0;GPa. Furthermore, the authors studied the phase transition and compressibility of the phases during decompression. <italic>Ab initio</italic> calculations were performed to support the characterization of the different BiN polymorphs.</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fchem.2023.1251774">Spektor et al.</ext-link> report on the impact of pressure in the ternary Na-Si-H system by computational structure prediction and <italic>in situ</italic> synchrotron diffraction studies. Various hypervalent hydridosilicate phases Na<sub>
<italic>m</italic>
</sub>SiH<sub>(4&#x2b;<italic>m</italic>)</sub> (<italic>m</italic> &#x3d; 1&#x2013;3) at comparatively low pressures of 0&#x2013;20&#xa0;GPa are expected, which could potentially be interesting in terms of superconductivity, ion conductivity, and hydrogen storage.</p>
<p>Investigations on the Dy-C system by <ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fchem.2023.1210081">Akbar et al.</ext-link> reveal the novel compounds Dy<sub>4</sub>C<sub>3</sub> and Dy<sub>3</sub>C<sub>2</sub>, obtained in a laser-heated diamond anvil cell by means of <italic>in situ</italic> single-crystal synchrotron X-ray diffraction. The corresponding sesquicarbide, Dy<sub>2</sub>C<sub>3</sub>, previously only known at ambient conditions, can also be obtained at such drastic conditions.</p>
<p>All contributions of this Research Topic clearly demonstrate, how &#x201c;extreme syntheses&#x201d; can facilitate the formation of hitherto unknown compounds, enrich the structural chemistry in the whole range from seemingly simple binary phases to complex multinary materials, and expand our general knowledge and understanding of chemistry.</p>
</body>
<back>
<sec id="s1">
<title>Author contributions</title>
<p>JB: Conceptualization, Visualization, Writing&#x2013;original draft, Writing&#x2013;review and editing. MB: Conceptualization, Visualization, Writing&#x2013;original draft, Writing&#x2013;review and editing. GH: Conceptualization, Visualization, Writing&#x2013;original draft, Writing&#x2013;review and editing. GT: Conceptualization, Visualization, Writing&#x2013;original draft, Writing&#x2013;review and editing.</p>
</sec>
<sec sec-type="COI-statement" id="s2">
<title>Conflict of interest</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec sec-type="disclaimer" id="s3">
<title>Publisher&#x2019;s note</title>
<p>All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.</p>
</sec>
</back>
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