Journal of Molecular Structure最新文献

A multifunctional Tb-MOF fluorescence sensor for selective detection of Er³⁺, nitrobenzene and tryptamine 用于选择性检测Er +、硝基苯和色胺的多功能Tb-MOF荧光传感器

IF 4.7 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2026-01-15 DOI: 10.1016/j.molstruc.2026.145379

Jing Ren, Xiao-Li Chen, Fan Liu, Yan-Tao Lei, Han-Lin Du, Ru Hong, Chen-Chao Wu

A novel terbium(III) metal-organic framework (Tb-MOF), namely: {[Tb₄(Pta)₂ (C₂O₄)₃(H₂O)₈]·7H₂O}ₙ was designed and hydrothermal synthesized based on 2, 4, 6 -tricarboxylic pyridine (H₃Pta) and 1, 2-dipiperidyl ethane (1, 2-bib) ligands. The structure was systematically characterized by single crystal X-ray diffraction, powder X-ray diffraction, elemental analysis and infrared spectroscopy. The structural analysis revealed that Tb-MOF contains two independently crystalline Tb³⁺ ions. Adjacent Tb³⁺ ions form a 1D ring-like chain structure through the coordination of oxalate ions (C₂O₄²⁻), and H₃Pta ligands further connect these chains, ultimately forming a 3D network framework. Tb-MOF exhibits excellent luminescent properties and can achieve highly sensitive and selective detection of Er³⁺, nitrobenzene (NB), and tryptamine (TRY) in aqueous solutions through fluorescence quenching effects. Interestingly, Tb-MOF can perform high-precision quantitative detection of TRY in aqueous solutions based on ratiometric fluorescence sensing. What is more valuable in terms of application is that we have successfully transformed Tb-MOF into a stable portable fluorescent test strip. When exposed to ultraviolet light (UV), this test strip can directly show the fluorescence changes with the naked eye, enabling rapid and visual on-site detection of TRY, significantly enhancing the convenience and practicability of the detection process. In addition, XPS, fluorescence lifetime, ultraviolet absorption and other principles are used to explore the mechanism of fluorescence quenching.

以2,4,6 -三羧基吡啶（H3Pta）和1,2 -二吡啶基乙烷（1,2 -bib）为配体，设计并合成了新型铽（III）金属有机骨架（Tb-MOF）： {[Tb4(Pta)2 （C₂O₄）3(H₂O)8]·7H2O}。采用单晶x射线衍射、粉末x射线衍射、元素分析和红外光谱对其结构进行了系统表征。结构分析表明，Tb- mof含有两种独立结晶的Tb³+离子。相邻的Tb³⁺通过草酸盐离子（C₂O₄²⁻）的配位形成1D环状链结构，H₃Pta配体进一步将这些链连接起来，最终形成3D网络框架。Tb-MOF具有优异的发光性能，可以通过荧光猝灭效应实现对水溶液中Er³⁺、硝基苯（NB）和色胺（TRY）的高灵敏度和选择性检测。有趣的是，Tb-MOF可以基于比例荧光传感对水溶液中的TRY进行高精度定量检测。更有应用价值的是，我们成功地将Tb-MOF转变为一种稳定的便携式荧光试纸条。在紫外线照射下，该试纸条可直接用肉眼显示荧光变化，实现了对TRY的快速、直观的现场检测，显著提高了检测过程的方便性和实用性。此外，利用XPS、荧光寿命、紫外吸收等原理探讨了荧光猝灭的机理。

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引用次数: 0

Spectroscopic and DFT studies of a quinazolinone heterocycle for DSSC energy and CCHF antiviral applications 喹唑啉酮杂环在DSSC能量和CCHF抗病毒应用中的光谱和DFT研究

IF 4.7 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2026-01-14 DOI: 10.1016/j.molstruc.2026.145325

Dalal Dlovan Sulaiman , Maryam Mustafa Muhammad , Myasar Kh. Ibrahim PhD. , Alya A. Dawood PhD. , Shireen R. Mohammed PhD.

A succinct and efficient synthetic route to 8,9-dihydro-6H-pyrido[2,1-b]quinazolin-11(7H)-one is developed. The compound was synthesized by condensing piperidin-2-one with methyl 2-aminobenzoate in the presence of phosphorus oxychloride and then by a one-step intramolecular cyclization. The target heterocycle was obtained as a white crystalline solid with an 86% yield. The resulting product was well characterized by IR, ¹H NMR, ¹³C NMR, DEPT, COSY, HSQC, and HRMS spectroscopic methods, and the obtained data revealed a high level of consistency between experimental and theoretical findings. The complementary DFT and TD-DFT studies also confirmed the suggested molecular structure and identified important electronic characteristics, such as high intramolecular charge-transfer (ICT) character and significant stabilization energies, which confirmed the overall structural integrity and stability of the compound. TD-DFT computations revealed strong π → π* transitions with large oscillator strengths, which are associated with the exceptional light-harvesting efficiency (LHE = 0.4016) in dichloromethane (DCM). This strong optical performance highlights the possibility of the compound as an effective sensitizer in dye-sensitized solar cells (DSSCs), making it a promising candidate in the development of solar cells in the next generation. Molecular docking experiments have shown high binding affinities to the oncogenic (cancer-related) protein target 4XH6 and the Crimean-Congo haemorrhagic fever virus (CCHFV) glycoprotein 3PRP with calculated binding energies of -8.5 kcal/mol, respectively, indicating potential promise as a lead structure in anticancer and antiviral drug development. It is worth noting that CCHFV is a major health threat in the region, as pointed out by the World Health Organization.

建立了一条简洁高效的合成8,9-二氢- 6h -吡啶[2,1-b]喹唑啉-11(7H)- 1的路线。该化合物是在氯氧磷存在下与2-氨基苯甲酸甲酯缩合，再经过一步分子内环化合成的。目标杂环为白色结晶固体，产率为86%。通过IR、¹H NMR、¹³C NMR、DEPT、COSY、HSQC和HRMS等光谱方法对产物进行了表征，所得数据与理论结果具有较高的一致性。互补DFT和TD-DFT研究也证实了所建议的分子结构，并确定了重要的电子特征，如高分子内电荷转移（ICT）特征和显著的稳定能，从而证实了该化合物的整体结构完整性和稳定性。TD-DFT计算表明，在二氯甲烷（DCM）中，π→π*跃迁具有较大的振子强度，这与出色的光收集效率（LHE = 0.4016）有关。这种强大的光学性能突出了该化合物作为染料敏化太阳能电池（DSSCs）的有效敏化剂的可能性，使其成为下一代太阳能电池发展的有希望的候选者。分子对接实验显示，该蛋白与致癌（癌症相关）蛋白靶点4XH6和克里米亚-刚果出血热病毒（CCHFV）糖蛋白3PRP具有较高的结合亲和性，计算出的结合能分别为-8.5 kcal/mol，表明其有潜力作为抗癌和抗病毒药物开发的先导结构。值得注意的是，正如世界卫生组织指出的那样，埃博拉病毒是该地区的一个主要健康威胁。

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引用次数: 0

Immobilization of Cu(II)-DEAS complex on MOF MIL-101(Cr)-NH2: A mesoporous heterogeneous catalyst for the synthesis of 3,5-disubstituted-1,2,4-triazoles MOF MIL-101(Cr)-NH2固定化Cu(II)-DEAS配合物：合成3,5-二取代-1,2,4-三唑的介孔非均相催化剂

IF 4.7 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2026-01-14 DOI: 10.1016/j.molstruc.2026.145382

Pritish Rajkumar Moon, Jyoti Prabha Kujur, Devendra Deo Pathak

Metal–organic frameworks (MOFs), have emerged as versatile platforms in heterogeneous catalysis because of their distinctive attributes, such as exceptional porosity, large surface area, high thermal stability, presence of tunable surface functionality, and unique geometric/electronic configurations. A copper(II)-DEAS immobilized metal–organic framework (MOF), MIL-101(Cr)@DEAS-Cu(II), 1, has been synthesized using 4-(diethylamino)salicylaldehyde (DEAS) as a coordinating ligand with Cu(II) on the surface of amine functionalized MOF, MIL-101(Cr)‑NH₂. The structure and the morphology of the immobilized MOF, 1, were comprehensively determined by FT-IR, XRD, XPS, SEM, TEM, EDX, elemental mapping, TGA, BET, and ICP-OES analysis, which confirmed the successful immobilization of Cu(II) onto the surface of the MOF framework. The propensity of the immobilized MOF, as a heterogeneous catalyst, was investigated in the one-pot synthesis of an array of 3,5-disubstituted-1,2,4-triazoles from benzyl amines and benzonitriles under solvent, base, and additive-free conditions. Under optimized reaction conditions, high product selectivity, rapid conversion of reactants, and high yields of products (up to 88%) were observed. The use of 1, as a heterogeneous catalyst, also aligns with the principles of green chemistry metrics in terms of AE (76%), E-factor (0.2), CE (79%), PMI (1.2), and RME (78%). The catalytic system benefits from mild reaction conditions, facile separation, and recyclability up to four cycles with insignificant loss in performance, highlighting its potential as an efficient and eco-friendly alternative to conventional homogeneous catalysts.

金属有机骨架（mof）由于其独特的特性，如特殊的孔隙率、大表面积、高热稳定性、可调节的表面功能以及独特的几何/电子结构，已成为多相催化领域的通用平台。以4-（二乙基氨基）水杨醛（DEAS）为配位体，在胺功能化MIL-101（Cr）‑NH2表面与Cu（II）配位，合成了铜(II)-DEAS固定化金属有机骨架（MOF） MIL-101（Cr）‑NH2。通过FT-IR、XRD、XPS、SEM、TEM、EDX、元素映射、TGA、BET、ICP-OES等分析手段对固定化MOF 1的结构和形貌进行了全面表征，证实了Cu（II）在MOF框架表面的成功固定化。在无溶剂、无碱和无添加剂的条件下，研究了固定化MOF作为非均相催化剂在苯胺和苯腈一锅合成一系列3,5-二取代-1,2,4-三唑的倾向。在优化后的反应条件下，产物选择性高，反应物转化率快，产物收率高（可达88%）。使用1作为多相催化剂，在AE（76%）、e因子（0.2）、CE（79%）、PMI（1.2）和RME（78%）方面也符合绿色化学指标的原则。该催化体系的优点是反应条件温和，易于分离，可循环使用长达四个循环，性能损失很小，突出了其作为传统均相催化剂的高效环保替代品的潜力。

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引用次数: 0

Dynamic hydrogen-bond inspired coating with enhanced interfacial mobility for integrated corrosion resistance and self-healing performance 具有增强界面迁移率的动态氢键激发涂层，具有综合耐腐蚀性和自愈性能

IF 4.7 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2026-01-14 DOI: 10.1016/j.molstruc.2026.145375

Xinyu Wang, Libo Tong, Miaomiao Li, Xiangjun Li, Yinxia Dong, Yuxin Gao, Kuaishe Wang

The incorporation of two-dimensional fillers restricts polymer chain mobility, thereby worsening the self-healing capability of organic coatings. To address this challenge, this study is inspired by dynamic hydrogen-bond strategy, an intrinsic self-healing composite coating of flexible-chain benzoxazine-derived Schiff base-modified epoxy resin with L-histidine-functionalized graphene oxide (EBP-fGO) is successfully prepared on the Mg alloy, which simultaneously enhances corrosion resistance and self‑healing performance. The self-healing property of EBP is derived from the synergistic effect of Schiff-based bonds topological rearrangement in the polymer and imidazole groups on fGO catalyzing benzoxazine ring-opening polymerization, promoting hydrogen bond formation and enhancing interfacial chain mobility near the fillers within the polymer matrix. Furthermore, fGO incorporation enhances corrosion protection via labyrinth effects, while its hydrogen bonding with the EBP matrix ensures optimal interfacial compatibility. After 21 days of immersion in 3.5 wt.% NaCl solution, the impedance modulus of this coating decreased by less than two orders of magnitude, from 4.15×10¹⁰ Ω·cm² to 6.12×10⁸ Ω·cm², demonstrating excellent corrosion resistance and durability. Besides, the EBP-fGO coating can achieve a self-healing efficiency of up to 92.6%, through a facile heat treatment. A unique strategy is thus proposed to enhance self-healing performance by promoting interfacial molecular mobility, offering a viable solution to reconcile the inherent conflict between enhanced barrier properties and restricted self-healing capability in two-dimensional filler-reinforced coatings for Mg alloy corrosion protection.

二维填料的掺入限制了聚合物链的迁移性，从而恶化了有机涂层的自修复能力。为了解决这一挑战，本研究受到动态氢键策略的启发，成功地在镁合金上制备了一种柔性链苯并杂嗪衍生的希夫碱改性环氧树脂与l -组氨酸功能化氧化石墨烯（EBP-fGO）的内在自修复复合涂层，同时增强了耐腐蚀性和自修复性能。EBP的自愈特性源于聚合物中希夫基键的拓扑重排和咪唑基团对氧化石墨烯的协同作用，催化苯并恶嗪开环聚合，促进氢键的形成，增强聚合物基体中填料附近界面链的迁移率。此外，fGO的加入通过迷宫效应增强了防腐能力，而它与EBP基体的氢键确保了最佳的界面相容性。在3.5 wt.% NaCl溶液中浸泡21天后，该涂层的阻抗模量下降了不到两个数量级，从4.15×1010 Ω·cm2降至6.12×108 Ω·cm2，表现出优异的耐腐蚀性和耐久性。此外，EBP-fGO涂层通过简单的热处理，可实现高达92.6%的自愈效率。因此，提出了一种独特的策略，通过提高界面分子迁移率来提高自修复性能，为解决二维填料增强镁合金防腐涂层中增强屏障性能和限制自修复能力之间的内在冲突提供了一种可行的解决方案。

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引用次数: 0

The first example of cyclotriphosphazenes as tyrosinase inhibitor: Synthesis, structure analysis, biological activity 环三磷杂烯作为酪氨酸酶抑制剂的第一例：合成、结构分析、生物活性

IF 4.7 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2026-01-14 DOI: 10.1016/j.molstruc.2026.145366

Elif Yıldız Gül , Mine Aksoy , Buse Köse , Aykut Öztekin , Bünyemin Çoşut , Esra Tanrıverdi Eçik

Since irregular skin pigmentation can trigger various diseases and is also considered an aesthetic concern, there is a growing demand for effective melanogenesis inhibitors. Tyrosinase, the key enzyme in the melanogenesis pathway, plays a central role in the treatment of hyperpigmentation by catalyzing the first and rate-limiting step of melanin biosynthesis. Although natural compounds are often preferred as tyrosinase inhibitors, their limited chemical stability and insufficient solubility have increased interest in synthetic inhibitors. The aim of this study was to design, synthesis and investigate the biological activity of the first cyclotriphosphazene-based tyrosinase inhibitor. In context, thiophene and thiomorpholine derivatives of cyclotriphosphazene (2–6) were synthesized, purified and structurally characterized using mass and NMR (³¹P, ¹H and ¹³C) techniques. The expected planar orientation of the cyclotriphosphazene core was confirmed by X-ray crystallographic analysis of compounds 4 and 5. The inhibitory activities of these compounds against tyrosinase were evaluated using in vitro and in silico approaches, and their pharmacokinetic properties were also assessed. Among the tested compounds, compound 2 exhibited the strongest inhibitory activity, with an IC₅₀ value of 0.083±0.000 mM (p<0.05). All of the compounds exhibited good radical scavenging and antibacterial activity. Overall, these findings indicate that the cyclotriphosphazene scaffold represents a promising building block for the design and synthesis of novel melanogenesis enzyme inhibitors.

由于不规则的皮肤色素沉着可以引发各种疾病，也被认为是审美问题，因此对有效的黑色素生成抑制剂的需求日益增长。酪氨酸酶是黑色素生成途径中的关键酶，通过催化黑色素生物合成的第一步和限速步骤，在色素沉着症的治疗中起着核心作用。虽然天然化合物通常是酪氨酸酶抑制剂的首选，但其有限的化学稳定性和溶解度不足增加了对合成抑制剂的兴趣。本研究的目的是设计、合成和研究第一种环三磷杂化酪氨酸酶抑制剂的生物活性。在此背景下，合成了噻吩和环三磷腈（2-6）的噻吩啉衍生物，并通过质量和核磁共振（31P， 1H和13C）技术对其进行了结构表征。化合物4和5的x射线晶体学分析证实了环三磷腈核的平面取向。采用体外和计算机模拟的方法评价了这些化合物对酪氨酸酶的抑制活性，并对其药代动力学性质进行了评价。在所测试的化合物中，化合物2表现出最强的抑制活性，IC₅0值为0.083±0.000 mM （p<0.05）。所有化合物均表现出良好的自由基清除和抗菌活性。总的来说，这些发现表明，环三磷腈支架代表了一个有希望的构建块设计和合成新的黑素生成酶抑制剂。

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引用次数: 0

Room-temperature columnar liquid crystal based on novel π-extended tetrathiafulvalene-pyridazine conjugates 基于新型π-扩展四噻吩-吡啶偶联物的室温柱状液晶

IF 4.7 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2026-01-14 DOI: 10.1016/j.molstruc.2026.145378

Ruibin Hou , Chao Xu , Yan Xia , Dongfeng Li

In order to reveal the relationships among molecular structure, self-assembly behavior and the organic electronic properties of columnar liquid crystalline, a series of pyridazine coupled ex-TTF derivatives 1a-c with varying amidated paraffinic side chains have been synthesized. The mesomorphic properties of these compounds were investigated by polarized optical microscopy (POM), differential scanning calorimetry (DSC), and variable temperature powder small-angle X-ray scatterings (SAXS). All the target compounds exhibits a single rectangular columnar mesophase in 22 and 68 °C temperature region. The reason why compounds 1a-c with folded “butterfly-like”conformation can form stable rectangular columnar phase is attributed to improved π-stacking as a result of a double H-bonding interaction between the peripheral amide groups, 1b forms a rectangular mesophase over a temperature range including room temperature.

为了揭示柱状液晶的分子结构、自组装行为和有机电子性能之间的关系，合成了一系列具有不同改性烷烃侧链的吡啶偶联前ttf衍生物1a-c。利用偏光显微镜（POM）、差示扫描量热仪（DSC）和变温粉末小角x射线散射（SAXS）研究了这些化合物的介形性质。所有目标化合物在22和68℃温度范围内均表现为单一的矩形柱状中间相。具有折叠“蝴蝶状”构象的化合物1a-c之所以能形成稳定的矩形柱状相，是由于外围酰胺基团之间的双h键相互作用改善了π堆积，1b在包括室温在内的温度范围内形成矩形中间相。

引用次数: 0

Synergistic thermal and luminescence investigation of dinuclear RE(III) complexes with fluorinated ligands: Combined TG-DSC/FTIR/MS analysis 含氟配体的双核RE（III）配合物的协同热发光研究：TG-DSC/FTIR/MS联合分析

IF 4.7 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2026-01-13 DOI: 10.1016/j.molstruc.2026.145358

Ruo-Bing Zhou , Jin-Jin Zhao , Ning Ren , Zhan-Hui Zhang , Jian-Jun Zhang

In this research work, four novel rare-earth complexes (La, Pr, Nd, Eu) were successfully designed and synthesized using 2,4-difluorobenzoic acid and 4,4′-dimethyl-2,2′-bipyridine as organic ligands. Single-crystal X-ray diffraction assays offered an in - depth revelation of the crystal structural features of the complexes, demonstrating that all four complexes exhibit highly consistent dinuclear structures with the same space group and similar coordination configurations. Further characterization techniques, including infrared spectroscopy (IR), Raman spectroscopy, powder X-ray diffraction (PXRD), proton nuclear magnetic resonance (¹H NMR), and scanning electron microscopy (SEM), confirmed the excellent crystallinity and structural uniformity of the products. The thermal decomposition behavior of this group of complexes was systematically studied with the help of TG - DTG - DSC/FTIR/MS coupled techniques. The thermal analysis results indicated that these complexes undergo multistage decomposition during programmed heating, and the characteristic gaseous products released at each stage were successfully identified through online Fourier-transform infrared spectroscopy (FTIR) and mass spectrometry (MS). Of particular interest, the photophysical properties of the Eu complex were studied in detail. Under ultraviolet excitation, the complex exhibited distinct Eu³⁺ characteristic emissions at 582 nm(⁵D₀ →⁷F₀₎ , 594 nm (⁵D₀→⁷F₁₎ ,619 nm (⁵D₀→⁷F₂₎ , 651 nm (⁵D₀→⁷F₃₎ , 694 nm (⁵D₀ →⁷F₄₎ . Luminescence lifetime measurements confirmed the complex's outstanding luminescence, evidencing its potential for luminescent applications.

本研究以2,4-二氟苯甲酸和4,4 ' -二甲基-2,2 ' -联吡啶为有机配体，成功地设计并合成了四种新型稀土配合物（La, Pr, Nd, Eu）。单晶x射线衍射分析深入揭示了配合物的晶体结构特征，表明这四种配合物具有高度一致的双核结构，具有相同的空间基团和相似的配位构型。进一步的表征技术，包括红外光谱（IR）、拉曼光谱（Raman）、粉末x射线衍射（PXRD）、质子核磁共振（¹H NMR）和扫描电子显微镜（SEM），证实了产品优异的结晶度和结构均匀性。采用TG - DTG - DSC/FTIR/MS耦合技术对该类配合物的热分解行为进行了系统的研究。热分析结果表明，这些配合物在程序升温过程中经历了多阶段分解，并通过在线傅里叶变换红外光谱（FTIR）和质谱（MS）成功地鉴定了每个阶段释放的特征气体产物。对铕配合物的光物理性质进行了详细的研究。在紫外激发下，Eu³⁺在582 nm（5D0→7F0）、594 nm（5D0→7F1）、619 nm（5D0→7F2）、651 nm（5D0→7F3）、694 nm（5D0→7F4）处表现出明显的特征发光。发光寿命测量证实了该复合物的杰出发光，证明了其发光应用的潜力。

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引用次数: 0

Spectroscopic, structural, optical, thermal, and dielectric properties of piperazinium 3-carboxy-4-hydroxybenzenesulfonate monohydrate 3-羧基-4-羟基苯磺酸一水合物哌嗪的光谱、结构、光学、热学和介电性质

IF 4.7 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2026-01-13 DOI: 10.1016/j.molstruc.2026.145356

R. Rajkumar , S. Suresh , Ramki Chakaravarthy , D. Pradhabhan , P. Selvaraju , P. Kavitha

The present work focuses on growth and characterization of Piperazinium 3-carboxy-4-hydroxybenzenesulfonate monohydrate (PSA) crystals, synthesized successfully using the slow evaporation solution growth method. XRD analysis confirmed the crystalline nature and revealed the unit cell parameters, indicating good structural order suitable for optical applications. The UV–Vis-NIR absorption spectrum is recorded in the range of 300–600 nm, exhibited a sharp cutoff at 335 nm and high transparency in the visible region and suitability of PSA crystal for optoelectronic and photonic applications. Thermogravimetric analysis is confirmed that the crystal remains thermally stable up to its decomposition temperature, ensuring durability under operational conditions. Microhardness measurement indicated that PSA crystal mechanically is a soft material and favoring easy to make device fabrication. Third-order nonlinear optical properties were investigated using the Z-scan technique yielded a nonlinear absorption coefficient (β) of 0.03 × 10⁻³ cm/W and a nonlinear refractive index (n₂) of 6.55 × 10⁻⁸ cm²/W confirming the materials strong third order nonlinearity. Dielectric studies revealed a stable frequency dependent dielectric response and physical- electronic parameters such as plasma energy (ℏωp), Penn gap (EP), Fermi energy (EF) and polarizability (α) were estimated to understand the electronic polarizability behavior. The combined structural integrity, optical transparency, thermal stability and third -order non-linear response suggest that PSA crystal is a promising candidate for optical limiting behavior, photonic switching and dielectric device applications.

本文研究了用慢蒸发溶液生长法制备的3-羧基-4-羟基苯磺酸一水合物（Piperazinium 3-羧基-4-羟基苯磺酸一水合物）结晶的生长和表征。XRD分析证实了该材料的晶体性质，揭示了其单晶胞参数，表明其具有良好的结构秩序，适合光学应用。紫外-可见-近红外吸收光谱在300-600 nm范围内，在335 nm处表现出明显的截止，在可见光区域具有高透明度，适合光电和光子应用。热重分析证实，晶体在其分解温度下保持热稳定，确保在操作条件下的耐久性。显微硬度测试表明，PSA晶体是一种柔软的材料，易于制作器件。用z -扫描技术研究了三阶非线性光学性质，得到了0.03 × 10⁻³cm/W的非线性吸收系数（β）和6.55 × 10⁻³cm²/W的非线性折射率（n₂），证实了材料具有强的三阶非线性。电介质研究揭示了稳定的频率相关介电响应，并估计了等离子体能量（p ω）、佩恩间隙（EP）、费米能量（EF）和极化率（α）等物理电子参数来了解电子极化率行为。PSA晶体的结构完整性、光学透明性、热稳定性和三阶非线性响应表明其在光限制行为、光子开关和介电器件等方面具有良好的应用前景。

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引用次数: 0

Synthesis, crystal structure and thermal properties of azole-based energetic materials 氮基含能材料的合成、晶体结构和热性能

IF 4.7 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2026-01-13 DOI: 10.1016/j.molstruc.2026.145346

Zhen-Li Yang , Ya-Dong Yao , Wu-Quan Meng , Zu-Jia Lu , Jian-Guo Zhang

The structures of 3-amino-5-hydrazino-1H-1,2,4-triazolium dihydrochloride (1) and 3-amino-5-hydrazino-1H-1,2,4-triazolium 5-nitraminotetrazolate (2) were further corroborated by single-crystal X-ray diffraction. Elemental analysis, mass spectra, FT-IR and differential scanning calorimetry studies were performed to characterize the synthesized energetic salts. New energetic derivatives, consisting of 1,2,4-triazole and tetrazole rings, explosophoric azo or nitroamino groups, and nitrogen-rich anion (cation), were successfully synthesized using straightforward and efficient chemical methodologies. The as-prepared energetic salts 2 and 3-amino-5-hydrazino-1H-1,2,4-triazolium 5,5′-azotetrazolate (3) possess advantageous measured densities and exceptionally elevated heats of formation, endowing them with outstanding detonation characteristics: detonation velocities of 8981 and 8082 m·s^-1, and detonation pressures of 32.9 and 27.1 GPa, respectively. The combination of these results, including insensitive mechanical sensitivity and notable high nitrogen contents ranging from 68.8% to 80.0%, suggests that these energetic salts hold potential as environmentally friendly substitutes for traditional explosives. Additionally, DSC and TG were used to probe the thermal-decomposition pathways of the salts, and an isoconversional protocol coupled with nonlinear regression furnished the corresponding differential kinetic mechanism functions.

单晶x射线衍射进一步证实了3-氨基-5-肼- 1h -1,2,4-三唑二盐酸盐(1)和3-氨基-5-肼- 1h -1,2,4-三唑-5-硝基氨基四唑酸盐(2)的结构。采用元素分析、质谱、红外光谱和差示扫描量热法对合成的含能盐进行了表征。利用简单有效的化学方法，成功地合成了由1,2,4-三唑和四唑环、爆炸性偶氮或硝基氨基和富氮阴离子（阳离子）组成的新的含能衍生物。制备的含能盐2和3-氨基-5-肼-h -1,2,4-三唑- 5,5 ' -氮四氮酸盐(3)具有良好的测量密度和极高的生成热，使其具有优异的爆轰特性：爆轰速度分别为8981和8082 m·s-1，爆轰压力分别为32.9和27.1 GPa。综合这些结果，包括不敏感的机械灵敏度和显著的高氮含量（68.8%至80.0%），表明这些含能盐具有作为传统炸药的环保替代品的潜力。此外，利用DSC和TG对盐的热分解途径进行了探讨，并结合非线性回归的等转换协议提供了相应的微分动力学机制函数。

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引用次数: 0

Dinuclear Zn(II) Schiff base complexes derived from m-phenylenediamine: Structure, photophysical properties and potential for selective detection of picric acid 间苯二胺衍生的双核Zn（II）希夫碱配合物：结构、光物理性质和选择性检测苦荞酸的潜力

IF 4.7 2区化学 Q2 CHEMISTRY, PHYSICAL

Journal of Molecular Structure

Pub Date : 2026-01-13 DOI: 10.1016/j.molstruc.2026.145335

Ninh Thi Minh Giang , Tran Ngoc Dung , Luc Van Meervelt , Tan Le Hoang Doan , Pham Do Chung , Le Thi Hong Hai

Five dinuclear Zn(II) complexes containing Schiff base ligands derived from m-phenylenediamine were synthesized and structurally characterized by elemental analysis, ESI-MS, IR, ¹H NMR, ¹³C NMR spectra and SC X-ray diffraction. In these complexes, Zn(II) ions coordinate to the ligands through N_imine and O_phenolic atoms in a 1:1 ratio. Photophysical studies revealed that all complexes exhibit a single emission band in the range of 453-527 nm, with ZnL5 displaying the strongest emission, ZnL2 the weakest and the remaining complexes showing intermediate emission efficiencies in the investigated solvents. In the solid state, the emission quantum yields decrease in the order ZnL5 (52.6 %) > ZnL4 (33.3 %) > ZnL1 (28.2 %) > ZnL2 (17 %) > ZnL3 (2 %). The excited-state lifetimes of the complexes in both the solid state (0.87-4.45 ns) and in solution (0.62-3.50 ns) fall within the nanosecond timescale, confirming the fluorescent nature of the emission process. Furthermore, ZnL5 exhibits a selective detection ability toward picric acid with a detection limit of 0.53 µM (approximately 121 ppb). Quantum-chemical calculations were carried out to examine the structural and optical properties of a series of Zn(II) complexes (ZnL1–ZnL5). The optimized ground- and excited-state geometries revealed that most complexes remain structurally rigid after excitation, while ZnL2 undergoes noticeable distortions that are consistent with a larger reorganization energy and weaker luminescence. Time-dependent DFT further confirms that fluorescence in all cases originates primarily from a HOMO → LUMO transition. Taken together, the results highlight ZnL5 as the most efficient red-emitting complex in the series, whereas ZnL2 is limited by nonradiative decay associated with structural relaxation.

以间苯二胺为原料合成了5个含席夫碱配体的双核Zn（II）配合物，并通过元素分析、ESI-MS、IR、1H NMR、13C NMR和SC - x衍射对其结构进行了表征。在这些配合物中，锌（II）离子以1:1的比例通过胺和酚原子与配体配位。光物理研究表明，所有配合物在453 ~ 527 nm范围内呈现单一发射带，其中ZnL5发射最强，ZnL2最弱，其余配合物在溶剂中表现出中等的发射效率。在固体状态下，发射量子产率依次为ZnL5 (52.6%) > ZnL4 (33.3%) > ZnL1 (28.2%) > ZnL2 (17%) > ZnL3（2%）。在固态（0.87-4.45 ns）和溶液（0.62-3.50 ns）中，配合物的激发态寿命都在纳秒级，证实了发射过程的荧光性质。此外，ZnL5对苦味酸具有选择性检测能力，检测限为0.53µM（约121 ppb）。采用量子化学计算方法研究了一系列Zn（II）配合物（ZnL1-ZnL5）的结构和光学性质。优化的基态和激发态几何结构表明，大多数配合物在激发后仍保持结构刚性，而ZnL2发生明显的畸变，这与重组能较大和发光较弱相一致。时间相关DFT进一步证实了所有情况下的荧光主要来源于HOMO→LUMO跃迁。综上所述，结果表明ZnL5是该系列中最有效的红发射配合物，而ZnL2则受到与结构弛豫相关的非辐射衰变的限制。

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