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DFT investigation of band gap and conductivity in pristine and doped Polyacetylene oligomers: A new extrapolation approach 原始和掺杂聚乙炔低聚物带隙和电导率的DFT研究:一种新的外推方法
IF 2.4 3区 化学 Q4 CHEMISTRY, PHYSICAL Pub Date : 2026-03-01 Epub Date: 2025-10-28 DOI: 10.1016/j.chemphys.2025.113004
Igor S. Kovalev , Alexander S. Novikov , Grigory V. Zyryanov
The electronic properties of polyacetylene (PA) isomers and their doped derivatives were investigated using density functional theory (DFT) at the PM3/B3LYP/def2-TZVP level. By studying a series of oligomers with increasing conjugation length, we determined the asymptotic band gaps to be 1.26 eV for trans-PA and 2.01 eV for cis-PA, rationalizing the higher conductivity of the trans-isomer. A novel nonlinear extrapolation method was developed to accurately predict the band gap of the infinite polymer from a minimal set of oligomer calculations. Furthermore, we demonstrate a dramatic band gap reduction—up to 97 %—upon p-doping via oxidation or bromination, and n-doping via deprotonation or reduction, confirming the transition to a metal-like state. The insulating nature of polytetrafluoroethylene (PTFE) was concurrently verified. Our findings provide a robust computational framework for screening optimal dopants to maximize PA conductivity.
利用密度泛函理论(DFT)研究了聚乙炔(PA)异构体及其掺杂衍生物在PM3/B3LYP/def2-TZVP能级上的电子性质。通过研究一系列共轭长度增加的低聚物,我们确定了反式pa的渐近带隙为1.26 eV,顺式pa的渐近带隙为2.01 eV,从而合理地解释了反式异构体的高导电性。提出了一种新颖的非线性外推方法,可以从最小的低聚物计算集中准确预测无限聚合物的带隙。此外,我们证明了通过氧化或溴化掺杂p-和通过去质子化或还原掺杂n-后,带隙减少了97%,证实了向类金属态的转变。同时验证了聚四氟乙烯(PTFE)的绝缘性能。我们的研究结果为筛选最佳掺杂剂以最大化PA电导率提供了一个强大的计算框架。
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引用次数: 0
Surface self-diffusion of ice under high hydrostatic pressure 高静水压力下冰的表面自扩散
IF 2.4 3区 化学 Q4 CHEMISTRY, PHYSICAL Pub Date : 2026-03-01 Epub Date: 2025-11-13 DOI: 10.1016/j.chemphys.2025.113025
Carlos L. Di Prinzio , Luis N. Gerez , Esteban Druetta , Pastor I. Achával , Guillermo G. Aguirre Varela
The temporal evolution of the width of a scratch on the basal plane (0001) of a pure ice single crystal was analyzed under hydrostatic pressures of 0.1 MPa and 10 MPa. The sample was immersed in ultrapure silicone oil at −5 °C to suppress sublimation. A custom-designed pressurized cell enabled the application of controlled hydrostatic pressure, while time-lapse imaging was conducted using an optical microscope equipped with a digital camera. Images of the scratch were acquired at 30-min intervals over a 24-h period. Quantitative analysis of the scratch profiles was performed using image processing software, allowing for the extraction of the time-dependent broadening of the scratch under the specified hydrostatic pressures. From this, the surface self-diffusion coefficient was determined, providing insight into pressure-dependent surface mass transport mechanisms in ice.
分析了纯冰单晶基面上划痕宽度(0001)在0.1 MPa和10 MPa静水压力下的时间演化规律。样品浸泡在- 5℃的超纯硅油中以抑制升华。定制设计的加压池可以控制静水压力,同时使用配备数码相机的光学显微镜进行延时成像。在24小时内每隔30分钟采集一次划痕图像。使用图像处理软件对划痕轮廓进行定量分析,以便在指定的静水压力下提取划痕随时间的扩展。由此,确定了表面自扩散系数,从而深入了解了冰中依赖压力的表面质量传递机制。
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引用次数: 0
Nonadiabatic dynamics study of the Sr+(4d2D) + H2(v = 0, 1; j = 0) reaction Sr+(4d2D) + H2(v = 0,1; j = 0)反应的非绝热动力学研究
IF 2.4 3区 化学 Q4 CHEMISTRY, PHYSICAL Pub Date : 2026-03-01 Epub Date: 2025-11-01 DOI: 10.1016/j.chemphys.2025.112995
Xiujuan Zhang, Wentao Li
Dynamics studies were performed on the Sr+(4d2D) + H2(v = 0, 1; j = 0) reaction based on diabatic potential energy surfaces. The results demonstrate that the reaction pathway Sr+(4d2D) + H2 is the primary mechanism for SrH+ formation, exhibiting significantly higher reactivity compared to the Sr+(5s2S) + H2 reaction. Calculated dynamical properties including reaction probabilities, integral cross sections, and differential cross sections for SrH+ formation, reveal that vibrational excitation of the H2 reactant substantially enhances reactivity. Furthermore, the differential cross sections are predominantly forward-scattered, indicating that the abstraction mechanism dominates the reaction.
基于非绝热势能面对Sr+(4d2D) + H2(v = 0,1; j = 0)反应进行了动力学研究。结果表明,Sr+(4d2D) + H2反应途径是SrH+的主要生成机制,其反应活性明显高于Sr+(5s2S) + H2反应。计算的动力学性质包括反应概率、SrH+生成的积分截面和微分截面,表明H2反应物的振动激发大大提高了反应活性。此外,微分截面主要是前向散射,表明萃取机制主导了反应。
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引用次数: 0
Dielectric characterization and thermodynamic analysis of iso-propyl acetate and Iso-amyl acetate with dimethyl sulphoxide binary mixtures using time domain reflectometry 用时域反射法表征醋酸异丙酯和醋酸异戊酯与二甲基亚砜二元混合物的介电性质和热力学分析
IF 2.4 3区 化学 Q4 CHEMISTRY, PHYSICAL Pub Date : 2026-03-01 Epub Date: 2025-11-10 DOI: 10.1016/j.chemphys.2025.113024
Pallavi D. Hambarde, Nitin P. Garad, Ashok C. Kumbharkhane
  • Investigated the dielectric properties and molecular interactions of isopropyl acetate (IPAc) and isoamyl acetate (IAA) with dimethyl sulfoxide (DMSO) binary mixtures using Time Domain Reflectometry (TDR) over 10 MHz–30 GHz.
  • Determined static dielectric constant (ε₀) and relaxation time (τ) by fitting complex permittivity spectra to the Cole–Davidson model with least squares fitting.
  • Evaluated molecular interactions and dielectric relaxation through Bruggeman factor, Kirkwood correlation factor, excess permittivity, and thermodynamic parameters.
  • Revealed structural differences and molecular interactions influenced by chain length and concentration, providing insights into dipole orientation and mixture behavior.
•使用时域反射法(TDR)在10 MHz-30 GHz范围内研究了醋酸异丙酯(IPAc)和醋酸异戊酯(IAA)与二甲亚砜(DMSO)二元混合物的介电性能和分子相互作用。•通过最小二乘法拟合Cole-Davidson模型的复介电常数谱来确定静态介电常数(ε 0)和弛豫时间(τ)。•通过Bruggeman因子、Kirkwood相关因子、过量介电常数和热力学参数评估分子相互作用和介电弛豫。•揭示了受链长和浓度影响的结构差异和分子相互作用,为偶极子取向和混合行为提供了见解。
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引用次数: 0
Micro-Raman study of H(l) precursor states of ultra-dense hydrogen H(0) 超致密氢H(0) H(l)前驱态的微拉曼研究
IF 2.4 3区 化学 Q4 CHEMISTRY, PHYSICAL Pub Date : 2026-03-01 Epub Date: 2025-11-08 DOI: 10.1016/j.chemphys.2025.113017
Leif Holmlid , Linnéa Gunnarsson
We show that micro-Raman spectroscopy is useful for studying hydrogen Rydberg Matter of the type H(l) at the generating catalyst surface. The excited hydrogen atoms comprising the H(RM) materials are observed in the anti-Stokes range, in the same way as the excited potassium atoms in potassium Rydberg Matter K(RM) were previously observed (Alpermann and Holmlid 2007). Atomic hydrogen transitions are observed at 320 K. This gives strong evidence for the formation of Rydberg Matter of atomic hydrogen on the potassium containing catalyst. Adsorbed hydrogen H2 molecules and other hydrogen containing molecules are observed in the Stokes range at shifts up to 4239 cm−1.
结果表明,微拉曼光谱可用于研究催化剂表面H(l)型氢里德堡物质。组成H(RM)材料的受激氢原子在反斯托克斯范围内被观察到,就像以前观察到的Rydberg物质K(RM)中的受激钾原子一样(Alpermann and Holmlid 2007)。在320 K时观察到原子氢跃迁。这为在含钾催化剂上形成氢原子里德伯物质提供了强有力的证据。吸附的H2分子和其他含氢分子在Stokes范围内的位移高达4239 cm−1。
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引用次数: 0
Planar pentacoordinate beryllium in neutral Be©Al5H5 species: Alkaline-earth aromaticity and covalent bonds 平面五坐标铍中性Be©Al5H5种:碱土芳香性和共价键
IF 2.4 3区 化学 Q4 CHEMISTRY, PHYSICAL Pub Date : 2026-03-01 Epub Date: 2025-10-23 DOI: 10.1016/j.chemphys.2025.112984
Hong-Lang Yu , Qiao-Qiao Yan , Wen-Xing Zhang , Yu Chen , Yang-Miao Ou , En-Dong Huang , Shao-Jie Li , Yi-Ran Li
We unveiled an unprecedented Be©Al5H5 motif featuring a planar pentacoordinate beryllium atom. This molecule exhibits robust electronic, thermodynamic, and dynamic stability up to 500 K. Our analysis confirmed that Be©Al5H5 exhibits σ/π double aromaticity. Both this aromaticity and the five outermost hydrogen atoms were indispensable for maintaining its molecular planarity. We further explored the substitution chemistry of Be©Al5H5 by replacing the outer hydrogen atoms with strong electron-withdrawing groups (-COOH). DFT and MP2(full) calculations confirmed that both the mono- and penta-substituted derivatives maintain rigid ppBe structures. The computed solvation free energies showed that the ppBe Be©Al5H5, Be©Al5H4(COOH) and Be©Al5(COOH)5 dissolve more readily in polar solvents. Calculations indicated that these compounds can be readily extracted from benzene or cyclohexane into the aqueous phase. Given its unique solubility in polar solvents and a strong potential for generating derivatives, we suggest that Be©Al5H5 could serve as a promising building block for aluminum‑beryllium covalent compounds.
我们推出了一个前所未有的以平面五坐标铍原子为特征的Be©Al5H5基序。该分子表现出强大的电子,热力学和动态稳定性高达500k。结果表明,Be©Al5H5具有σ/π双芳构性。这种芳香性和最外层的五个氢原子对于保持分子的平面性是必不可少的。我们进一步探索了Be©Al5H5的取代化学,用强吸电子基团(-COOH)取代外层氢原子。DFT和MP2(全)计算证实,单取代和五取代衍生物都保持刚性ppBe结构。计算的溶剂化自由能表明,ppBe Be©Al5H5、Be©Al5H4(COOH)和Be©Al5(COOH)5更容易在极性溶剂中溶解。计算表明,这些化合物可以很容易地从苯或环己烷中提取到水相中。鉴于其在极性溶剂中的独特溶解度和生成衍生物的强大潜力,我们认为Be©Al5H5可以作为铝铍共价化合物的有希望的构建块。
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引用次数: 0
Biosorption of Lead (II) and cadmium (II) ions from aqueous solution by buckwheat (Fagopyrum Esculentum) hulls biosorbent: kinetic, equilibrium and thermodynamic studies 荞麦壳生物吸附剂对铅(II)和镉(II)离子的生物吸附:动力学、平衡和热力学研究
IF 2.4 3区 化学 Q4 CHEMISTRY, PHYSICAL Pub Date : 2026-03-01 Epub Date: 2025-10-27 DOI: 10.1016/j.chemphys.2025.112997
Tayyab Tahir , Rūta Druteikienė , Zita Žukauskaitė , Jūratė Vaičiūnienė , Aušra Selskienė , Ilja Ignatjev , Muhammad Adnan
In this study buckwheat hull was used as an efficient, cheap and environmentally safe for the removal of Pb(II) and Cd(II) from an aqueous solution through optimizing various experimental parameters such as temperature (25–50 °C), solution pH (2–6 for Pb(II) and 2–7 for Cd(II)), amount of buckwheat hulls (0.1–0.35 g), initial Pb(II) and Cd(II) concentration (5–400 mg L−1) and contact time (30–1440 min). SEM, FTIR, EDX, and pHpzc measurements were used to analyze buckwheat hulls before and after biosorption. Kinetic data fitted best to the pseudo-second-order model due to higher values of R2 (R2Pb(II) = 0.999 and R2Cd(II) = 0.999). Equilibrium data matched the Langmuir model, yielding sorption capacities of 87.72 mg·g−1 for Pb(II) and 23.2 mg·g−1 for Cd(II), indicating monolayer adsorption. Analysis of thermodynamic parameters, revealed the non-spontaneous and exothermic characteristics of the removal of Pb(II) and Cd(II) by buckwheat hulls.
本研究通过优化温度(25-50℃)、溶液pH (Pb(II)为2-6、Cd(II)为2-7)、荞麦壳用量(0.1-0.35 g)、初始Pb(II)和Cd(II)浓度(5-400 mg L−1)和接触时间(30-1440 min)等实验参数,将荞麦壳作为高效、廉价、环保的水溶液中Pb(II)和Cd(II)的脱除剂。利用扫描电镜(SEM)、红外光谱(FTIR)、EDX和pHpzc等测量方法对生物吸附前后的荞麦壳进行了分析。由于R2较高(R2Pb(II) = 0.999, R2Cd(II) = 0.999),动力学数据最符合伪二阶模型。平衡数据符合Langmuir模型,Pb(II)的吸附量为87.72 mg·g−1,Cd(II)的吸附量为23.2 mg·g−1,表明其为单层吸附。热力学参数分析揭示了荞麦壳去除Pb(II)和Cd(II)的非自发和放热特性。
{"title":"Biosorption of Lead (II) and cadmium (II) ions from aqueous solution by buckwheat (Fagopyrum Esculentum) hulls biosorbent: kinetic, equilibrium and thermodynamic studies","authors":"Tayyab Tahir ,&nbsp;Rūta Druteikienė ,&nbsp;Zita Žukauskaitė ,&nbsp;Jūratė Vaičiūnienė ,&nbsp;Aušra Selskienė ,&nbsp;Ilja Ignatjev ,&nbsp;Muhammad Adnan","doi":"10.1016/j.chemphys.2025.112997","DOIUrl":"10.1016/j.chemphys.2025.112997","url":null,"abstract":"<div><div>In this study buckwheat hull was used as an efficient, cheap and environmentally safe for the removal of Pb(II) and Cd(II) from an aqueous solution through optimizing various experimental parameters such as temperature (25–50 °C), solution pH (2–6 for Pb(II) and 2–7 for Cd(II)), amount of buckwheat hulls (0.1–0.35 g), initial Pb(II) and Cd(II) concentration (5–400 mg L<sup>−1</sup>) and contact time (30–1440 min). SEM, FTIR, EDX, and pH<sub>pzc</sub> measurements were used to analyze buckwheat hulls before and after biosorption. Kinetic data fitted best to the pseudo-second-order model due to higher values of R<sup>2</sup> (R<sup>2</sup><sub>Pb(II)</sub> = 0.999 and R<sup>2</sup><sub>Cd(II)</sub> = 0.999). Equilibrium data matched the Langmuir model, yielding sorption capacities of 87.72 mg·g<sup>−1</sup> for Pb(II) and 23.2 mg·g<sup>−1</sup> for Cd(II), indicating monolayer adsorption. Analysis of thermodynamic parameters, revealed the non-spontaneous and exothermic characteristics of the removal of Pb(II) and Cd(II) by buckwheat hulls.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"602 ","pages":"Article 112997"},"PeriodicalIF":2.4,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Thermally stable 2D AlTlF4: A combined DFT and AIMD study of structural, electronic, thermal, and optical properties 热稳定二维AlTlF4:结构、电子、热学和光学性质的DFT和AIMD联合研究
IF 2.4 3区 化学 Q4 CHEMISTRY, PHYSICAL Pub Date : 2026-03-01 Epub Date: 2025-10-21 DOI: 10.1016/j.chemphys.2025.112980
Yousif Hussein Azeez , Nzar Rauf Abdullah
This study offers the first comprehensive investigation of the structural, electronic, thermal, and optical characteristics of the mixed metal fluoride AlTlF4 by density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) simulations. The negative formation energy of -3.11eV for AlTlF4 signifies energetic stability, whereas phonon dispersion analysis demonstrates the lack of negative frequencies, thereby affirming its dynamic stability. Furthermore, the AIMD simulation confirms its thermal stability. Electronic structure simulations reveal a substantial indirect band gap of 5.42 eV (GGA) and 6.75 eV (HSE06), characterized by flat valence bands predominantly comprised of F-2p states and narrow conduction bands derived from Tl-6p orbitals, indicative of a robust ionic insulator. Thermal study demonstrates distinct regimes in heat capacity and entropy, influenced by low-frequency Tl–F vibrations and high-frequency Al–F phonons. The smooth, continuous nature of these curves confirms the absence of phase transitions within the studied temperature range, underscoring the material’s thermodynamic stability. Analysis of optical properties reveals a broad transparency window below 5.92 eV using GGA functional, confirming AlTlF4’s potential as a UV-transparent material for protective coatings and optical components. The pronounced anisotropic absorption in the ultraviolet (6-8 eV) and deep-ultraviolet (12-14 eV) regions, particularly the enhanced response for y/z-polarized light, suggests specific applicability in polarization-sensitive deep-UV optoelectronics. This directional absorption behavior, combined with the material’s thermal stability, enables the design of specialized photodetectors for extreme environment applications.
本研究首次通过密度泛函理论(DFT)计算和从头算分子动力学(AIMD)模拟对混合氟化金属AlTlF4的结构、电子、热学和光学特性进行了全面的研究。AlTlF4的负形成能为-3.11eV,表明其能量稳定,而声子色散分析表明其缺乏负频率,从而肯定了其动态稳定性。此外,AIMD仿真验证了其热稳定性。电子结构模拟结果显示,GGA和HSE06的间接带隙分别为5.42 eV和6.75 eV,其特征是主要由F-2p态组成的价带和由Tl-6p轨道衍生的窄导带,表明该离子绝缘体是坚固的。热学研究表明,在低频Tl-F振动和高频Al-F声子的影响下,热容量和熵有不同的变化。这些曲线的光滑,连续的性质证实了在研究的温度范围内没有相变,强调了材料的热力学稳定性。光学性质分析表明,使用GGA功能,AlTlF4具有5.92 eV以下的宽透明窗口,这证实了AlTlF4作为保护涂层和光学元件的紫外线透明材料的潜力。在紫外(6-8 eV)和深紫外(12-14 eV)区域明显的各向异性吸收,特别是对y/z偏振光的增强响应,表明在偏振敏感的深紫外光电子学中具有特殊的适用性。这种定向吸收行为与材料的热稳定性相结合,使设计用于极端环境应用的专用光电探测器成为可能。
{"title":"Thermally stable 2D AlTlF4: A combined DFT and AIMD study of structural, electronic, thermal, and optical properties","authors":"Yousif Hussein Azeez ,&nbsp;Nzar Rauf Abdullah","doi":"10.1016/j.chemphys.2025.112980","DOIUrl":"10.1016/j.chemphys.2025.112980","url":null,"abstract":"<div><div>This study offers the first comprehensive investigation of the structural, electronic, thermal, and optical characteristics of the mixed metal fluoride AlTlF<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> by density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) simulations. The negative formation energy of -<span><math><mrow><mn>3</mn><mo>.</mo><mn>11</mn><mspace></mspace><mi>eV</mi></mrow></math></span> for AlTlF<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span> signifies energetic stability, whereas phonon dispersion analysis demonstrates the lack of negative frequencies, thereby affirming its dynamic stability. Furthermore, the AIMD simulation confirms its thermal stability. Electronic structure simulations reveal a substantial indirect band gap of 5.42 eV (GGA) and 6.75 eV (HSE06), characterized by flat valence bands predominantly comprised of F-<span><math><mrow><mn>2</mn><mi>p</mi></mrow></math></span> states and narrow conduction bands derived from Tl-<span><math><mrow><mn>6</mn><mi>p</mi></mrow></math></span> orbitals, indicative of a robust ionic insulator. Thermal study demonstrates distinct regimes in heat capacity and entropy, influenced by low-frequency Tl–F vibrations and high-frequency Al–F phonons. The smooth, continuous nature of these curves confirms the absence of phase transitions within the studied temperature range, underscoring the material’s thermodynamic stability. Analysis of optical properties reveals a broad transparency window below 5.92 eV using GGA functional, confirming AlTlF<span><math><msub><mrow></mrow><mrow><mn>4</mn></mrow></msub></math></span>’s potential as a UV-transparent material for protective coatings and optical components. The pronounced anisotropic absorption in the ultraviolet (6-8 eV) and deep-ultraviolet (12-14 eV) regions, particularly the enhanced response for <span><math><mi>y</mi></math></span>/<span><math><mi>z</mi></math></span>-polarized light, suggests specific applicability in polarization-sensitive deep-UV optoelectronics. This directional absorption behavior, combined with the material’s thermal stability, enables the design of specialized photodetectors for extreme environment applications.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"602 ","pages":"Article 112980"},"PeriodicalIF":2.4,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145340415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Exploring the differences in thermal decomposition mechanisms between crystalline and nanoscale 3-nitro-1,2,4-triazole-5-one by molecular dynamics simulations 通过分子动力学模拟探索晶体级和纳米级3-硝基-1,2,4-三唑-5- 1热分解机制的差异
IF 2.4 3区 化学 Q4 CHEMISTRY, PHYSICAL Pub Date : 2026-03-01 Epub Date: 2025-11-03 DOI: 10.1016/j.chemphys.2025.113014
Jincheng Ji , Simin Zhu , Changxin Li , Weihua Zhu
Density-functional tight-binding molecular dynamics simulations (DFTB-MD) were used to simulate the thermal decomposition of crystalline and nanoscale 3-nitro-1,2,4-triazole-5-one (NTO) at different temperatures. The results of MD simulations indicate that the initial decomposition mechanism of both crystalline and nanoscale NTO are dominated by the single molecule decomposition. In crystalline NTO, the rearrangement of -NO2 and direct ring opening are the dominant decomposition pathways. The C-NO2 homolysis is the main decomposition path for nanoscale NTO, and the decomposition mechanism of nanoscale NTO is significantly influenced by temperature. The activation energy for the decomposition of crystalline NTO is 15.59 kcal·mol−1, which is higher than that of 9.81 kcal·mol−1 for nanoscale NTO, indicating that the activation energy for the decomposition of nanoscale explosives is lower than that of crystalline explosives in this work. This study could provide theoretical guidance for understanding of the thermal reactions of explosives in different aggregation states.
采用密度功能紧密结合分子动力学模拟(DFTB-MD)模拟了晶体和纳米级3-硝基-1,2,4-三唑-5-酮(NTO)在不同温度下的热分解。MD模拟结果表明,晶体级和纳米级NTO的初始分解机制均以单分子分解为主。在结晶NTO中,-NO2的重排和直接开环是主要的分解途径。C-NO2均解是纳米级NTO的主要分解途径,温度对纳米级NTO的分解机理有显著影响。晶体型NTO的分解活化能为15.59 kcal·mol−1,高于纳米级NTO的9.81 kcal·mol−1,说明本文中纳米级炸药的分解活化能低于晶体型炸药。该研究可为理解炸药在不同聚集状态下的热反应提供理论指导。
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引用次数: 0
Urchin-like cl-doped NiCo bimetallic fluorides for high-performance asymmetric supercapacitors 用于高性能非对称超级电容器的海胆样cl掺杂NiCo双金属氟化物
IF 2.4 3区 化学 Q4 CHEMISTRY, PHYSICAL Pub Date : 2026-03-01 Epub Date: 2025-10-29 DOI: 10.1016/j.chemphys.2025.113002
Feng Guo , BianTao Wu , YanXin Yang , ZhangSheng Liu , PeiZhong Feng
Cl-doped NiCo bimetallic fluorides are fabricated via a solvothermal process and subsequent fluoridization. During the fluoridization, the flower-like precursor NiCo-Cl layered double hydroxide (LDH) tends to be transformed into urchin-like morphology. As-obtained (Ni,Co)(F1-xClx)2 samples (NCFC-x, x = 0, 10, 15, 20 and 25) exhibit excellent electrochemical performance, among which NCFC-20 provides the highest specific capacitance of 2569 F g−1 at a current density of 2 A g−1 and remarkable cycling stability of 79.0 % capacity retention after 7000 cycles. Correspondingly, the assembled NCFC-20//active carbon asymmetric supercapacitor delivers a high energy density (37.3 Wh kg−1) at a power density of 850 W kg−1 and outstanding cycling stability of 88.7 % capacity retention after 6000 cycles. The superior electrochemical performance of NCFC-20 can be attributed to the synergistic effect of typical urchin-like structure and Cl ion doping. Such a material shows an enormous potential for applications in high-performance supercapacitor.
采用溶剂热法和随后的氟化法制备了掺杂cl的NiCo双金属氟化物。在氟化过程中,花状前体NiCo-Cl层状双氢氧化物(LDH)倾向于转变为海胆状形态。所得(Ni,Co)(F1-xClx)2样品(NCFC-x, x = 0, 10, 15, 20和25)表现出优异的电化学性能,其中NCFC-20在电流密度为2 a g−1时的最高比电容为2569 F g−1,循环7000次后的循环稳定性为79.0%。相应的,组装的NCFC-20//活性炭不对称超级电容器在850 W kg - 1的功率密度下具有较高的能量密度(37.3 Wh kg - 1),并且在6000次循环后具有88.7%的容量保持率。NCFC-20优异的电化学性能可归因于典型的胆状结构和Cl离子掺杂的协同作用。这种材料在高性能超级电容器中显示出巨大的应用潜力。
{"title":"Urchin-like cl-doped NiCo bimetallic fluorides for high-performance asymmetric supercapacitors","authors":"Feng Guo ,&nbsp;BianTao Wu ,&nbsp;YanXin Yang ,&nbsp;ZhangSheng Liu ,&nbsp;PeiZhong Feng","doi":"10.1016/j.chemphys.2025.113002","DOIUrl":"10.1016/j.chemphys.2025.113002","url":null,"abstract":"<div><div>Cl-doped NiCo bimetallic fluorides are fabricated via a solvothermal process and subsequent fluoridization. During the fluoridization, the flower-like precursor NiCo-Cl layered double hydroxide (LDH) tends to be transformed into urchin-like morphology. As-obtained (Ni,Co)(F<sub>1-x</sub>Cl<sub>x</sub>)<sub>2</sub> samples (NCFC-x, x = 0, 10, 15, 20 and 25) exhibit excellent electrochemical performance, among which NCFC-20 provides the highest specific capacitance of 2569 F g<sup>−1</sup> at a current density of 2 A g<sup>−1</sup> and remarkable cycling stability of 79.0 % capacity retention after 7000 cycles. Correspondingly, the assembled NCFC-20//active carbon asymmetric supercapacitor delivers a high energy density (37.3 Wh kg<sup>−1</sup>) at a power density of 850 W kg<sup>−1</sup> and outstanding cycling stability of 88.7 % capacity retention after 6000 cycles. The superior electrochemical performance of NCFC-20 can be attributed to the synergistic effect of typical urchin-like structure and Cl ion doping. Such a material shows an enormous potential for applications in high-performance supercapacitor.</div></div>","PeriodicalId":272,"journal":{"name":"Chemical Physics","volume":"602 ","pages":"Article 113002"},"PeriodicalIF":2.4,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145425050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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Chemical Physics
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