{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T09:07:05Z","timestamp":1789117625561,"version":"build-2803163510"},"reference-count":41,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T00:00:00Z","timestamp":1789084800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["22375190"],"award-info":[{"award-number":["22375190"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["22375190"],"award-info":[{"award-number":["22375190"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Addressing the inherent trade-off between energy content and safety remains a long-standing priority in the field of energetic materials. In this work, we employed a straightforward isomer design strategy, synthesizing a structural isomer of 4-amino-7-methyl-5-nitro-7H-pyrazolo[3,4-d][1,2,3]triazine-2-oxide (MPTO), namely 4-methylamino-5-nitro-7H-pyrazolo[3,4-d][1,2,3]triazine-2-oxide (1). Despite involving only a subtle difference in the connectivity of substituents, compound 1 exhibits a dramatically distinct crystal packing mode compared to MPTO. This structural variation directly translates into a remarkable performance enhancement: compound 1 not only delivers superior detonation velocity (8193 m\u00b7s\u22121) and detonation pressure (25.6 GPa) relative to the parent compound, but also shows substantially reduced mechanical sensitivities (impact sensitivity &gt; 20 J, friction sensitivity &gt; 360 N), while maintaining favorable thermal stability (296 \u00b0C). This study not only provides a promising candidate energetic molecule with well-balanced overall performance, but also highlights, from a crystal engineering perspective, the significant potential of isomer design in fine-tuning the properties of fused-ring energetic materials.<\/jats:p>","DOI":"10.3390\/molecules31183203","type":"journal-article","created":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T08:17:42Z","timestamp":1789114662000},"page":"3203","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Isomerism as a Design Tool: Tuning the Energy\u2013Safety Balance of a Fused Pyrazolo-Triazine N-Oxide Energetic Material"],"prefix":"10.3390","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-7243-7349","authenticated-orcid":false,"given":"Haohuang","family":"Wang","sequence":"first","affiliation":[{"name":"Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621999, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Ziwu","family":"Cai","sequence":"additional","affiliation":[{"name":"Extreme-Environment-Resistant Materials Key Laboratory of Sichuan Province, Sichuan University of Science & Engineering, Zigong 643000, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Tianyu","family":"Jiang","sequence":"additional","affiliation":[{"name":"Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621999, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"}]},{"given":"Yuteng","family":"Cao","sequence":"additional","affiliation":[{"name":"Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621999, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"}]},{"given":"Wenquan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang 621999, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1038\/s41467-017-00286-0","article-title":"A promising high-energy-density material","volume":"8","author":"Zhang","year":"2017","journal-title":"Nat. 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