Chemistry of Materials最新文献

{"title":"Tunable Magnetotransport across Competing Magnetic Phases in the Distorted Kagome Antiferromagnet HoPtSn","authors":"Abhinav Agarwal,&nbsp;Snehashish Chatterjee,&nbsp;Andrzej Ptok,&nbsp;Orest Pavlosiuk,&nbsp;Piotr Wiśniewski,&nbsp;Dariusz Kaczorowski","doi":"10.1021/acs.chemmater.6c00030","DOIUrl":"10.1021/acs.chemmater.6c00030","url":null,"abstract":"<p>Competing magneticphases in frustrated systems provide a fertileground for unusual magnetic and electronic responses owing to theirsensitivity to external perturbations. The distorted kagome antiferromagnetHoPtSn is an example of such a system, exhibiting successive magnetictransitions and multiple field-induced metamagnetic states at lowtemperatures. Here, we combine magnetic susceptibility, heat capacity,magnetotransport, and magnetization under hydrostatic pressure measurementson single crystals to investigate the interplay between the competingmagnetic phases in HoPtSn. At ambient pressure, HoPtSn undergoes twomagnetic transitions at <em>T</em>_N1 ≈ 7.3K and <em>T</em>_N2 ≈ 2.7 K. The lower-temperaturetransition is accompanied by pronounced thermal and magnetic hysteresis,indicating its first-order character. Magnetization measurements reveala series of field-induced transitions and a strongly anisotropic low-temperaturephase diagram. Correspondingly, the magnetotransport exhibits sharpanomalies across the metamagnetic transitions together with clearfield-history dependence, while Hall resistivity measurements revealadditional features that emerge within the ordered state. These resultspoint to a strong coupling between electronic transport and magneticreconstruction. Hydrostatic pressure leaves <em>T</em>_N1 nearly unchanged, while it gradually shifts <em>T</em>_N2 to higher temperatures, indicating that the competingmagnetic phases respond differently to lattice compression, whilethe first-order transition remains robust throughout the investigatedpressure range. Electronic structure calculations reveal several Dirac-likecrossings near the Fermi level, suggesting possible interplay betweenthese features and the complex magnetic phase space. Taken together,our results show that HoPtSn hosts a delicate balance between competingmagnetic states, whose reconstruction leaves distinct signatures inthe transport properties and can be continuously tuned by pressure.These findings highlight distorted kagome antiferromagnets as a promisingplatform for exploring the interplay between magnetic phase competitionand electronic transport.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"38 19","pages":"9754–9762"},"PeriodicalIF":7.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148973923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Low-Temperature Combustion Synthesis of Metals and Metal Oxides via Isobutylene-Generating Complexing Agents","authors":"Thomas W. Colburn,&nbsp;Abigail Carbone,&nbsp;David W. Collinson,&nbsp;Robert D. Miller,&nbsp;Reinhold H. Dauskardt","doi":"10.1021/acs.chemmater.6c01946","DOIUrl":"10.1021/acs.chemmater.6c01946","url":null,"abstract":"<p>Solution combustion synthesis (SCS) is a low-temperaturesynthesistechnique leveraging a highly exothermic combustion reaction betweena metal complexed by an organic fuel and oxidant (e.g., nitrate) togenerate metals and metal compounds such as oxides, nitrides, andcarbides at reduced applied temperatures compared to conventionalsolution methods. However, many ideal hydrocarbon fuels for low-temperaturecombustion processes are too volatile and noncoordinating to metalcations in solution, making them poorly suited for SCS. Here, we presentSCS complexing agents, which contain <em>t</em>-butyl esterfunctionality capable of generating isobutylene in situ at low appliedtemperatures, which acts as a potent fuel in the combustion process.We form four important oxides and metal/oxide combined nanostructures:InO_x, MnO_x, NiO_x, and CoO_x at applied temperatures &lt;150 °C including the formationof InOx at &lt;80 °C which is, to our knowledge, the lowest purelyheat-initiated SCS reaction observed to date. This work reveals thatisobutylene-generating fuels, particularly for the indium cation,are a powerful tool for applications demanding oxides at low formationtemperatures.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"38 19","pages":"10242–10250"},"PeriodicalIF":7.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148973925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microwave-Assisted Facile Synthesis and Microenvironment Engineering of Enaminone COFs for Efficient Photocatalytic H2O2 Production","authors":"Sagarmani Rasaily,&nbsp;Nayan Sarkar,&nbsp;Sukalyan Chatterjee,&nbsp;Saurabh Vinod Parmar,&nbsp;Sudip Maity,&nbsp;Dipanjan Majumder,&nbsp;Anirban Roy,&nbsp;Vidya Avasare,&nbsp;Sujit K. Ghosh","doi":"10.1021/acs.chemmater.6c01601","DOIUrl":"10.1021/acs.chemmater.6c01601","url":null,"abstract":"<p>Covalent organic frameworks (COFs) have emerged as promisingmetal-freephotocatalysts; however, their widespread application is often hinderedby the time-consuming solvothermal preparation. Developing rapid andcost-effective routes to highly crystalline COFs is therefore essentialfor expanding their practical utility. In this regard, microwave-assistedsynthesis offers a distinct advantage over conventional solvothermalmethods by shortening reaction times from days to minutes while simultaneouslyimproving crystallinity. Here, we report a microwave-assisted strategyfor synthesizing enaminone-COFs via the Michael addition-eliminationreaction, achieving &gt;90% yields within 60 min. The developed microwave-assistedstrategy demonstrated broad versatility by enabling the synthesisof six distinct enaminone COFs. Notably, the microwave-synthesizedCOFs exhibited physical properties similar to previously reportedframeworks. Among the synthesized enaminone COFs, COF-Tz-MW and COF-Bz-MWwere rationally engineered with tunable nitrogen content, creatingdistinct local microenvironments that modulate the acceptor–donor–acceptor(A–D–A) charge-transfer pathway for efficient photocatalyticH₂O₂ synthesis. This molecular-level variationwas systematically investigated to elucidate its influence on chargedistribution and photophysical properties, revealing a clear structure–reactivitycorrelation of enaminone-COFs in H₂O₂ photosynthesis.Notably, the COF-Bz-MW demonstrated effective charge separation andsuperior H₂O₂ production performance with aproduction rate of 8.70 mmol g^–1 h^–1 from blue LED-H₂O–O₂. Theoretical studiesrevealed that the enaminone moiety coupled with the benzene core aminecreates an optimized A–D–A configuration, enhancingO₂-adsorption and promoting efficient photocatalytic H₂O₂ production. Our work pioneers a paradigm forfacile and rapid synthesis of enaminone COFs, while demonstratingN-site microenvironment engineering as an effective strategy to advanceCOF-based photocatalysts for efficient photocatalytic H₂O₂ production.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"38 19","pages":"10062–10074"},"PeriodicalIF":7.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149003387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Melting Point Depression and Glass-Forming Abilities in Pb- and Sn-Based Hybrid Perovskites with a Nonprimary Ammonium Cation","authors":"Yi Xie,&nbsp;Rayan Chakraborty,&nbsp;Akash Singh,&nbsp;Timothy M. McWhorter,&nbsp;AM Milinda Abeykoon,&nbsp;Daniel Olds,&nbsp;Volker Blum,&nbsp;David B. Mitzi","doi":"10.1021/acs.chemmater.6c01289","DOIUrl":"https://doi.org/10.1021/acs.chemmater.6c01289","url":null,"abstract":"<p>Two-dimensional organic–inorganicperovskitescan attainlower congruent melting temperatures (<em>T</em>_<em>m</em>) through compositional design, including, for example,by incorporating nonprimary ammonium cations, enabling solvent-freemelt processing and glass formation. Although Pb- and Sn-based systemshave been explored, the structural and mechanistic origins of theirdistinct thermal behaviors remain poorly understood. Here, startingfrom the model (MC3I)₂PbI₄ (MC3I = <em>N</em>-methyliodopropylammonium), we demonstrate that replacing Pb withSn lowers <em>T</em>_<em>m</em> to 86.0°C (359.2 K) and markedly modulates glass-forming ability. Temperature-dependentsingle-crystal X-ray diffraction, pair distribution function, andfirst-principles electron localization functions provide continuousstructural insights from 100 K to the molten state, enabling directcomparison across the melting transition and correlation with thermalbehavior. We demonstrate that Sn substitution yields larger structuraldistortions (e.g., associated with increased lone-pair stereoactivity),selectively elongated and more ionic Sn–I bonds, reduced tolerancefor atomic thermal vibrations, and more accessible atomic arrangementsin the melt, resulting in a higher melting entropy (Δ<em>S</em>_<em>m</em>) and lower <em>T</em>_<em>m</em>. Both Pb and Sn compounds exhibit robustmelt stability over 50 crystal-melt-glass cycles without discernibledecomposition, while showing increased glass-forming propensity. Prolongedmelt dwelling effectively promotes vitrification in the Sn compound,despite its relatively lower glass-forming ability relative to thePb-based system.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"38 19","pages":"9916–9928"},"PeriodicalIF":7.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149173855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-Damping Elastomers Enabled by Precise Regulation of Polyborosiloxane Relaxation Behaviors","authors":"Fu-Long Gong,&nbsp;Xiaotong Shu,&nbsp;Wenqing Lv,&nbsp;Shuang Long,&nbsp;Bin Huang,&nbsp;Pingping Lou,&nbsp;Xuezhong Zhang,&nbsp;Hua-Feng Fei,&nbsp;Zhijie Zhang","doi":"10.1021/acs.chemmater.6c02055","DOIUrl":"https://doi.org/10.1021/acs.chemmater.6c02055","url":null,"abstract":"<p>Viscoelastic polymer materials exhibiting high dampingcapacitywithin a specified frequency–temperature range effectivelydissipate mechanical energy as heat, thereby mitigating damage inducedby vibrations and impact loads. However, developing a convenient methodfor precisely designing damping materials with tunable energy dissipationproperties across a desired frequency–temperature range remainschallenging. Herein, we present a strategy for fabricating high-dampingpolyborosiloxane (PBS) elastomers (PBSEs) with tunable damping performanceacross a specified frequency–temperature range. This is achievedby precisely modulating the PBS relaxation behavior─specifically,through systematic variation of both the B–O bond content andthe molecular weight of the PDMS diol precursors. We found that theresultant PBSEs exhibit controllable high-damping performance acrossan ultrawide frequency range (tan <em>δ</em> &gt; 0.3,10^–3 to 10² Hz) and temperature range(tan <em>δ</em> = 0.5–0.6, −20 to 150°C). Moreover, PBSEs exhibit excellent impact-protective performancecompared with commercial materials and attenuate impact force by morethan 95%. This unique design concept will provide a convenient approachto developing advanced damping materials.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"38 19","pages":"10308–10318"},"PeriodicalIF":7.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149173976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bidirectional Photocurrents Induced by Ferrocene Spacers in Layered Hybrid Perovskites","authors":"Melina Dahlke,&nbsp;Yaşar Krysiak,&nbsp;Onno Strolka,&nbsp;Jannika Lauth,&nbsp;Marvin Treger,&nbsp;Carolin König,&nbsp;Sebastian Polarz","doi":"10.1021/acs.chemmater.6c02198","DOIUrl":"https://doi.org/10.1021/acs.chemmater.6c02198","url":null,"abstract":"<p>As our technology advances, the demand for more functionalsemiconductormaterials has grown. In layered hybrid perovskites, an enhanced functionalitycan be achieved by introducing molecular switches as spacers. Thesespacers permit the reversible modulation of the semiconductor properties,which can, for example, induce distinct photoresponses. In particular,negative and positive photocurrents (NPC, PPC) hold much potentialfor multistate photosensing. However, NPC in a single-layered hybridperovskite material remains currently unknown. Here, we report onNPC and PPC in layered Dion-Jacobson-like and Ruddlesden–Popperhybrid perovskites induced by a switchable ferrocene-based spacer.Electronic communication in the form of charge transfer between theferrocene moiety and the perovskite framework was confirmed via transientabsorption spectroscopy. Under an external electric field, the ferrocene-inducedcharge carriers are rearranged into space charge zones, which quenchesthe conductivity, resulting in the NPC. This charge carrier arrangementis prohibited in Ruddlesden–Popper phases due to the presenceof a van der Waals gap, leading to the PPC. Furthermore, NPC can alsobe realized for hybrid perovskites with different band gaps by adjustingbromide and iodide contents, highlighting the potential of spacer-inducedphotocurrents as the semiconductor properties can be tuned as needed.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"38 19","pages":"10341–10350"},"PeriodicalIF":7.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149174059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Activating\u0000Interstitial Oxygen Conduction in Sr3V2O8 Palmierite Oxides Through Minimal\u0000Mo-Substitution","authors":"Abdulkadir Olatunbosun Biffo,Anastasia K. Lavrinenko,Hailin Ma,Shengnan Zhang,Till Frümling,Alexandros Vasileiadis,Theodosios Famprikis,Pedro B. Groszewicz","doi":"10.1021/acs.chemmater.6c01807","DOIUrl":"https://doi.org/10.1021/acs.chemmater.6c01807","url":null,"abstract":"Abstract The palmierite oxides are a promising family of ion conductors, and understanding how compositional modification affects their structure and, in turn, their ionic conductivity is pivotal for unlocking high ionic conductivity in these solid electrolytes. Here, we investigate the Sr3V2-xMoxO8+x/2 series (0 ≤ x ≤ 0.4), establishing a solubility limit at x = 0.2, and demonstrating that Mo-substituted compositions exhibit bulk O2– conductivity approximately 2 orders of magnitude higher than the pristine composition at 600 °C. Combined X-ray and neutron diffraction refinement shows little change in the average crystallographic structure, prompting questions about its local structure and dynamics. Using ab initio molecular dynamics, bond-valence site-energy calculations, and 51V and 17O solid-state nuclear magnetic resonance spectroscopy supported by density functional theory calculations, we demonstrate that Mo6+ incorporation generates a new oxygen environment consistent with the formation of a charge-compensating interstitial O3 site. While V5+ remains tetrahedrally coordinated throughout the series, Mo6+ exhibits both MoO4 and distorted trigonal bipyramidal MoO5 coordination polyhedra, with the latter arising from the occupation of O3. This O3 site is proposed to bridge neighboring MOn polyhedra along the ab-plane, shortening the O2– jump distances and shifting the conduction mechanism from a 3D cooperative rotational mechanism to a 2D interstitial-based one.","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"412 1","pages":""},"PeriodicalIF":8.6,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149209462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrogels for Soft Robotics and Bio-Integrated Devices: Review on Self-Healing to Intelligent Actuation","authors":"Kesaba Charan Bishoyi,&nbsp;Asit Kumar Pradhan,&nbsp;Subhangi Devadarshini Sahoo","doi":"10.1021/acs.chemmater.6c01296","DOIUrl":"10.1021/acs.chemmater.6c01296","url":null,"abstract":"<p>Self-healing and shape memory hydrogels have emergedas a transformativeclass of materials poised to reform next-generation bioelectronics,soft robotics, and actuation systems. By combining biocompatibility,mechanical tunability, and autonomous repair properties, these materialsoffer unique advantages for designing resilient and multifunctionaldevices that mimic the adaptability and responsiveness of biologicaltissues. This review provides a comprehensive analysis of the recentprogress in the molecular design, network architectures, fabricationstrategies, and functional integration of self-healing hydrogels intosmart devices. Emphasis is placed on understanding the dynamic bondingmechanisms involving reversible covalent and supra-molecular interactionsthat impart self-repair capabilities while balancing mechanical robustness,conductivity, and biocompatibility. Special attention is given tohighlighting how self-healing and shape memory functionalities enhancedevice durability, responsiveness, and long-term performance. We furtherexplore the role of stimuli-responsive mechanisms, such as pH, temperature,and electrical signals, in enabling adaptive actuation and signaltransduction. Additionally, the key challenges such as healing speed,operational stability in physiological environments, and seamlessmultifunctionality have been discussed and outline future directionstoward programmable, autonomous, and multifunctional hydrogel systems.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"38 19","pages":"9676–9694"},"PeriodicalIF":7.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148973834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Topology-Controlled Proton Transport in Thermotropic Liquid-Crystalline Acid–Base Complexes","authors":"Chengyang Liu,&nbsp;Masafumi Yoshio","doi":"10.1021/acs.chemmater.6c01661","DOIUrl":"10.1021/acs.chemmater.6c01661","url":null,"abstract":"<p>The constructionof efficient proton-transport channels is of greatinterest for applications in fuel cells and biological systems. Inparticular, three-dimensionally interconnected bicontinuous networksin liquid-crystalline (LC) assemblies provide an attractive platformfor enabling efficient proton transport. However, the realizationof anhydrous proton-conducting gyroid cubic LC assemblies remainsa significant challenge. Here we report a strategy to control thedimensionality and connectivity of proton-transport pathways throughBrønsted base-acid complexation. A series of wedge-shaped amphiphilesbearing a common imidazole/amide headgroup and varying alkyl-chainlengths (<strong>IM8</strong>, <strong>IM10</strong>, and <strong>IM12</strong>) were complexed with two Brønsted acids with distinct anioncharacteristics, benzenesulfonic acid (<strong>BS</strong>) and bis(trifluoromethanesulfonyl)imide(<strong>HTFSI</strong>). Systematic variation of acid fraction and temperatureunder nonhumidified conditions revealed that <strong>IM12</strong> exhibitscurvature-driven polymorphism, including a hexagonal columnar (Col_h) phase at low acid fractions and a bicontinuous <em>Ia3̅d</em> gyroid (Gyr) phase at intermediate acid contents, whereas <strong>IM8</strong> and <strong>IM10</strong> form only smectic A (SmA) phasesover broad compositions. ¹H NMR titration indicates thatimidazole protonation and ion-pair formation dominate the base–acidequilibrium, while weaker secondary interactions involve the amidegroup. Variable-temperature FT-IR measurements reveal progressivestrengthening of the polar interaction network upon cooling. Proton-transportmeasurements show that the Gyr base–acid complexes exhibitthe highest conductivity, the lowest apparent activation energy, andweaker viscosity–conductivity coupling in Walden-type analysis.Dielectric modulus and rheological measurements further support fasterbulk relaxation and a more robust elastic framework in the gyroidphase. These findings establish design principles for proton-conductingLC materials based on curvature-controlled, three-dimensionally interconnectedionophilic nanochannels formed through base–acid complexation.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"38 19","pages":"10106–10117"},"PeriodicalIF":7.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149010456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic Bending of Carbodiimide Anions Derives Uniaxial Negative Thermal Expansion in ZnNCN","authors":"Taichi Nagai,&nbsp;Eri Arita,&nbsp;Akira Miura,&nbsp;Mikio Higuchi,&nbsp;Takafumi Yamamoto,&nbsp;Kotaro Fujii,&nbsp;Masatomo Yashima,&nbsp;Kazuki Shitara,&nbsp;Akihide Kuwabara,&nbsp;Yuji Masubuchi","doi":"10.1021/acs.chemmater.6c01606","DOIUrl":"10.1021/acs.chemmater.6c01606","url":null,"abstract":"<p>Materials exhibiting negative thermal expansion (NTE),characterizedby anomalous lattice contractions upon heating, have attracted considerableattention because of the unique attendant changes in crystal structure.A wide variety of compounds, including metal oxides, fluorides, andcyanides, show this phenomenon as a consequence of open-frameworkstructures. However, compounds containing linear, triatomic dumbbell-likecarbodiimide anion NCN^2– have received less attention.Herein, we report that ZnNCN exhibits uniaxial NTE along the <em>c</em>-axis with a coefficient of −5.34(1) × 10^–6 K^–1 together with a coefficientof 4.12(3) × 10^–6 K^–1 alongthe <em>a</em>-axis at 300 K. Structural refinement usingneutron diffraction data acquired at different temperatures indicatesa contraction of the averaged N–N separation along the <em>c</em>-axis. Pair distribution functions (PDFs) generated fromneutron total scattering data reveal that the ∠NCN angle decreasesfrom 175° at 30 K to 160.5° at 673 K. Ab initio moleculardynamics calculations examining the local structure indicate an increasedproportion of dynamical transverse bending of NCN^2– anions, consistent with the PDF analysis. At higher temperatures,enhanced intramolecular bending of the anions is suggested to induceNTE along the <em>c</em>-axis in ZnNCN. Dynamical bendingof molecular anions provides a design strategy for NTE materials,thereby expanding the scope of molecular-anion-based compounds.</p>","PeriodicalId":33,"journal":{"name":"Chemistry of Materials","volume":"38 19","pages":"10075–10084"},"PeriodicalIF":7.1,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149019640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}