CrystEngComm最新文献

{"title":"High-contrast switching of dielectric properties via a reversible isomerization phase transition in 1H-2,4-diamino-6-phenyl-1,3,5-triazine perchlorate","authors":"Ping-Yuan Zhang, Jia Song, Su-Jing Zhang, Guang-Ying Zhang, Xiang-Yu Shi, Ze-Feng Yang, Zheng-Hui Hu and Ji-Xing Gao","doi":"10.1039/D6CE00241B","DOIUrl":"https://doi.org/10.1039/D6CE00241B","url":null,"abstract":"<p >Dielectric response materials, which exhibit reversible and tunable dielectric properties under external stimuli, have shown broad application prospects in information storage, sensors, and smart switches. In this study, a novel molecular crystal, DAPT·ClO<small>₄</small> (DAPT = 1<em>H</em>-2,4-diamino-6-phenyl-1,3,5-triazine), was successfully synthesized and systematically characterized. Infrared spectroscopy confirmed the successful formation of the target compound with characteristic functional groups. Thermogravimetric analysis revealed its excellent thermal stability up to approximately 450 K. Powder X-ray diffraction patterns matched well with the simulated data, confirming its high phase purity and good crystallinity. The differential scanning calorimetry curves exhibit a reversible pair of exothermic and endothermic peaks at approximately 223 K and 248 K. Variable-temperature single-crystal analysis reveals an isomorphous phase transition, with both high- and low-temperature phases crystallizing in the <em>P</em>2<small>₁</small>/<em>c</em> space group. Dielectric measurements show that the dielectric constant changes by nearly twice near the phase transition temperature at 1 MHz, highlighting its potential as a dielectric switching material. Through the analysis of the structures, it was found that the slight distortion of perchloric acid and the weakening of hydrogen bond forces around the guest cations jointly induced the phase transition. This study provides new ideas for designing molecular crystals with switchable dielectric properties and lays a foundation for the development of advanced functional materials.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 24","pages":" 3797-3802"},"PeriodicalIF":2.4,"publicationDate":"2026-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148285400","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}

{"title":"Investigation on local structures of Si–Cr-based solvents via ab initio molecular dynamics","authors":"Guangda Chen, Zhongnan Guo, Wenlong Wu, Zihai Li, Peirou Ji, Lishi Chen, Yunfan Yang, Da Sheng, Hui Li and Wenxia Yuan","doi":"10.1039/D6CE00089D","DOIUrl":"https://doi.org/10.1039/D6CE00089D","url":null,"abstract":"<p >For the top-seeded solution growth (TSSG) method, an emerging technique for SiC single crystal fabrication, the high-temperature behavior of Si–Cr-based solvents after dissolving carbon (C) is critical for designing and optimizing the growth process. However, an atomic-scale study of the local structures of Si–Cr-based solvents is still lacking. In this work, the <em>ab initio</em> molecular dynamics (AIMD) method was employed to investigate the local structures and C diffusion behavior in Si–Cr-based solvents. It is revealed that the addition of Ce or Al strengthens the Cr–C interactions while weakening Si–C. Remarkably, C atoms in the Si–Cr solvent tend to aggregate, forming C–C dimers, whereas the addition of Ce/Al effectively suppresses this aggregation. The diffusion coefficients further indicate enhanced C migration in the Si–Cr–Ce and Si–Cr–Al solvents compared to the Si–Cr binary system. Moreover, the local structures of solvents are influenced by the crystalline facets of the seed, with the C diffusion occurring more rapidly in solvents in contact with the Si-face. Our work provides the first atomic-scale analysis of local structures of solvents and the diffusion behavior of the solute C atoms, which provides a new perspective for understanding the regulation mechanism of SiC high temperature solution growth.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 25","pages":" 3884-3891"},"PeriodicalIF":2.4,"publicationDate":"2026-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148336612","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}

{"title":"Polymorphism-dependent mechanochromic luminescence in a donor–acceptor compound","authors":"Zhi-Bo Fan, Jia-Wang Hou and Fei Tong","doi":"10.1039/D6CE00258G","DOIUrl":"https://doi.org/10.1039/D6CE00258G","url":null,"abstract":"<p >A mechanochromic luminogen material, MC-TPA, was synthesized, and two crystals (<strong>type Y</strong> and <strong>type O</strong>) exhibiting different fluorescence emissions were obtained through crystallization. Following mechanical grinding, <strong>type Y</strong> displayed red-shifted emission. Upon exposure to different solvent vapors, the amorphous phase selectively transformed into <strong>type Y</strong> or <strong>type O</strong>, respectively. Structural and theoretical analyses indicate that the divergent luminescence properties were governed by distinct packing modes and intermolecular interactions.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 22","pages":" 3443-3448"},"PeriodicalIF":2.6,"publicationDate":"2026-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148193695","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}

{"title":"Novel high-concentration Eu3+-doped CaLaNbWO8 red phosphors with high brightness for w-LEDs and temperature sensing applications","authors":"Daiman Zhu, Heyan Zhang, Kai Li and Yongli Li","doi":"10.1039/D6CE00055J","DOIUrl":"https://doi.org/10.1039/D6CE00055J","url":null,"abstract":"<p >Increasing demand for phosphor-converted white light-emitting diodes (w-LEDs) with high color rendering index (CRI) and low correlated color temperature (CCT) is driving the development of high-performance phosphors. In this work, a series of novel Eu<small>³⁺</small>-doped CaLaNbWO<small>₈</small> red phosphors was prepared <em>via</em> a high-temperature solid-state reaction approach. The pure phase was confirmed by XRD analysis. Eu<small>³⁺</small> content was optimized to be 70%, which was higher than that of most Eu<small>³⁺</small>-related systems. A detailed investigation about the luminescence properties of the optimal CaLa<small>_0.3</small>NbWO<small>₈</small>:0.7Eu<small>³⁺</small> red phosphor was conducted, including excitation, emission and temperature-dependence spectra. The excitation spectrum demonstrated a broad range extending from 200 to 500 nm, encompassing a substantial broad band originating from W<small>⁶⁺</small>–O<small>²⁻</small> charge transfer and numerous narrow bands attributable to Eu<small>³⁺</small> characteristic transitions. Photoluminescence (PL) studies demonstrated the occurrence of Eu<small>³⁺</small> characteristic transitions, with the main peak observed at 614 nm under ultraviolet irradiation. Moreover, an increase in the concentration of Eu<small>³⁺</small> ions was shown to result in a decline in the fluorescence time, which can be attributed to the enhancement of energy transfer among Eu<small>³⁺</small> ions. Thermal stability analysis indicated that the CaLa<small>_0.3</small>NbWO<small>₈</small>:0.7Eu<small>³⁺</small> phosphor maintained 80% (433 K) of its initial intensity at 298 K, while the different emission peaks of Eu<small>³⁺</small> presented diverse decreasing trends with increasing temperature. Consequently, the temperature sensing properties were also investigated, attaining a maximal absolute sensitivity (<em>S</em><small>_a</small>) of 10.32% K<small>⁻¹</small> and relative sensitivity (<em>S</em><small>_r</small>) of 1.75% K<small>⁻¹</small> by employing FIR<small>_614/655</small>, thereby signifying its promising potential in non-contact thermometers. Furthermore, the phosphor employed in the fabrication of a w-LED exhibited a correlated color temperature (CCT) of 5893 K and a color rendering index (CRI) of 87.1, in conjunction with a near-ultraviolet (NUV) 395 nm chip. These results indicated the promising potential of w-LEDs and fluorescence thermometers in practical applications.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 24","pages":" 3762-3774"},"PeriodicalIF":2.4,"publicationDate":"2026-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148285379","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}

{"title":"Influence of point defects on the optical properties of La3Nb0.5Ga5.5O14 crystals","authors":"Jindong Chen, Hongxu Gu, Shusen Yang, Ning Ye, Kui Wu and Dazhi Lu","doi":"10.1039/D6CE00090H","DOIUrl":"https://doi.org/10.1039/D6CE00090H","url":null,"abstract":"<p >Point defects critically influence the optical performance of langasite-type La<small>₃</small>Nb<small>_0.5</small>Ga<small>_5.5</small>O<small>₁₄</small> (LGN) crystals, yet their nature and evolution under different growth conditions remain unclear. Here, we systematically investigated the defect structure in LGN crystals grown under N<small>₂</small> and N<small>₂</small> + 2% O<small>₂</small> atmospheres and after subsequent vacuum annealing. The results revealed that both gallium vacancies and oxygen vacancies intrinsically existed in LGN, while their relative concentrations strongly depended on the growth atmosphere. In LGN grown under an N<small>₂</small> + O<small>₂</small> atmosphere, excess oxygen vacancies formed F and F<small>⁺</small> centers, giving rise to characteristic absorption bands at ∼480 nm and ∼335 nm, respectively, whereas these color centers were largely suppressed in crystals grown under a pure N<small>₂</small> atmosphere. A distinct absorption band at ∼1860 nm was attributed to the electronic transitions involving gallium vacancy-induced shallow acceptor levels, as supported by first-principles calculations. Vacuum annealing selectively eliminated the F centers but preserved the F<small>⁺</small> centers, which was attributed to their deeper defect levels and stronger electron localization. Based on these results, a defect formation mechanism governed by the competitive evaporation of Ga<small>₂</small>O and O<small>₂</small> is proposed. Furthermore, dislocation analysis revealed that screw dislocations dominated on the (2−10) surface, while edge dislocations prevailed on the (001) surface, with a higher dislocation density observed in crystals grown under an oxygen-containing atmosphere.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 24","pages":" 3775-3784"},"PeriodicalIF":2.4,"publicationDate":"2026-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148285399","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}

{"title":"Balancing energy and safety in a nitropyrazole-based melt-cast explosive carrier: 1,4-dimethyl-3,5-dinitropyrazole","authors":"Jin Yue, Zu-jia Lu, Cong Li, Qi-yao Yu and Jian-guo Zhang","doi":"10.1039/D6CE00253F","DOIUrl":"https://doi.org/10.1039/D6CE00253F","url":null,"abstract":"<p >The development of melt-cast explosives with balanced energy, safety, and processability remains a critical challenge due to the inherent trade-offs among these properties. Herein, we report a rationally designed melt-cast explosive carrier, 1,4-dimethyl-3,5-dinitropyrazole (DMDNP), synthesized <em>via</em> a one-step nitration from commercially available precursors. DMDNP exhibits a favorable melting point (101.0 °C), high thermal stability (<em>T</em><small>_d</small> = 300.6 °C), and a density of 1.638 g cm<small>⁻³</small> at 118 K. The detonation performance, based on EXPLO5 calculations, reaches a velocity of 7082 m s<small>⁻¹</small> and a pressure of 19.2 GPa, outperforming traditional TNT and significantly exceeding DNAN. Notably, DMDNP demonstrates low mechanical sensitivities (IS = 50 J, FS &gt; 360 N, and <em>E</em><small>₅₀</small> = 9.3 J), attributed to a synergistic combination of high bond dissociation energy, herringbone crystal packing, and a low proportion of unfavorable O⋯O and O⋯N intermolecular contacts. With straightforward synthesis, favorable thermal behavior, enhanced detonation performance, and low sensitivity, DMDNP exhibits well-balanced properties and holds promise for further application studies as a next generation melt-cast explosive carrier.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 22","pages":" 3458-3465"},"PeriodicalIF":2.6,"publicationDate":"2026-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148193718","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}

{"title":"Correlating thermal history to structural integrity and cycling stability in NMC 111 cathodes","authors":"Jeffrey S. Ovens, Rex Chen, Yingzi Feng, Majid Talebiesfandarani, Stephen A. Campbell and Byron D. Gates","doi":"10.1039/D6CE00043F","DOIUrl":"https://doi.org/10.1039/D6CE00043F","url":null,"abstract":"<p >Thermal treatment is critical for determining the structure and stability of layered cathode materials, which in turn affect the performance of lithium-ion batteries. This study systematically investigated the thermal evolution of NMC 111 cathode materials synthesized from prelithiated precursors. Thermogravimetric analysis and variable-temperature X-ray diffraction were employed to monitor phase transitions and mass loss over a wide temperature range. The material transformed from a calcite-type carbonate to rock salt and subsequently to the layered NMC 111 structure, with crystallization largely complete near 800 °C. Cation mixing can begin around 500 °C but remains reversible upon cooling if the sample is heated to 800 °C or lower. In contrast, prolonged thermal soaking at high temperatures (≥900 °C) causes irreversible structural degradation, including the emergence of Li-deficient spinel phases attributed to lithium volatilization. An optimal soak temperature of 800 °C was identified, balancing high crystallinity with minimal irreversible cation mixing. Material synthesized at 800 °C also exhibited greater cycling stability than materials processed at higher temperatures. A dwell time of ∼6 hours is sufficient to produce high-quality NMC 111 materials. Balancing dwell time and upper-temperature thresholds is essential during synthesis. These findings offer practical guidance for optimizing thermal treatments used to manufacture layered cathodes for lithium-ion batteries.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 22","pages":" 3526-3538"},"PeriodicalIF":2.6,"publicationDate":"2026-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2026/ce/d6ce00043f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148193725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single-crystals of B ← N based covalent organic polymers with dual photosensitive motifs for photocatalytic dye degradation","authors":"Xinpeng He, Linkuo Li and Qichun Zhang","doi":"10.1039/D6CE00276E","DOIUrl":"https://doi.org/10.1039/D6CE00276E","url":null,"abstract":"<p >Single crystals of a covalent organic polymer (CityU-69) with dual photosensitive motifs were prepared <em>via</em> B ← N bonds. Single crystal X-ray diffraction (SCXRD) analysis showed that CityU-69 has a zig-zag chain-like configuration. CityU-69 displays excellent photocatalytic activity for dye degradation, benefiting from fast charge transfer and synergistic effects between the two motifs.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 21","pages":" 3293-3297"},"PeriodicalIF":2.6,"publicationDate":"2026-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148141601","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}

{"title":"Energy band engineering in CsXBr3(X = Ge, Sn)/Janus MoSSe heterojunctions for photovoltaic applications","authors":"Yixiao Gu, Chao Xie, Lang Yang, Han Tan, Yunkai Wu and Xu Wang","doi":"10.1039/D6CE00178E","DOIUrl":"https://doi.org/10.1039/D6CE00178E","url":null,"abstract":"<p >Perovskite-based materials enable the stacking of different components through van der Waals (vdW) interactions, offering unprecedented flexibility in designing functional materials. By integrating perovskite CsXBr<small>₃</small>, (X = Ge, Sn) with two-dimensional transition metal dichalcogenides (TMDs) to form heterojunctions, synergistic effects are achieved, significantly enhancing the performance of optoelectronic devices. Using first-principles calculations based on density functional theory, we systematically investigate the electronic structure, interfacial charge transfer, and optical properties. The electronic structure of perovskite and MoSSe is preserved after heterojunction formation, and both type-I and type-II band alignments are attainable depending on the contact configuration, catering to different applications. Furthermore, charge accumulation near the interface generates an internal electric field that facilitates electron–hole separation. The formation of the heterojunction not only broadens and enhances the perovskite's light-absorption spectrum but, under strain modulation, the type-II configuration exhibits a theoretical power conversion efficiency (PCE) of up to 33.4% under idealized conditions based on the Scharber model. These findings unveil the interfacial characteristics of CsXBr<small>₃</small>/MoSSe heterostructures and highlight their potential for advanced optoelectronic applications.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 21","pages":" 3353-3363"},"PeriodicalIF":2.6,"publicationDate":"2026-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148141609","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}

{"title":"Crystal-facet anisotropy dictates the alkali dissolution behavior of struvite","authors":"Yu Wei, Pengping Li, Zhihong Fan, Xinxing Zhang, Mingfeng Zhong, Pingan Liu and Zhijie Zhang","doi":"10.1039/D6CE00181E","DOIUrl":"https://doi.org/10.1039/D6CE00181E","url":null,"abstract":"<p >The long-term durability of magnesium phosphate cement (MPC), particularly in repair applications, is critically limited by the chemical stability of its primary hydration product, struvite (MgNH<small>₄</small>PO<small>₄</small>·6H<small>₂</small>O), in alkaline environments. While struvite exhibits diverse crystal morphologies, the mechanism underlying how these morphological variations influence its dissolution behavior under strong alkali conditions remains unclear. This study systematically investigates the dissolution kinetics and microscopic mechanisms of four representative struvite morphologies – rodlike, petal-like, prismatic, and dendritic – in a highly alkaline environment (pH = 12). A combination of characterization techniques, including SEM, XRD, FT-IR, ICP-OES, and TG-DTG, coupled with theoretical calculations of surface energy and adsorption energy, was employed. The results reveal an anisotropic dissolution law governed by the preferential exposure of specific crystal facets. The rodlike morphology, possessing the highest proportion of the active [002] face, exhibits the lowest surface energy and the strongest adsorption energy for OH<small>⁻</small>. This leads to the preferential leaching of NH<small>₄</small><small>⁺</small>, subsequent collapse of the crystal structure, and ultimate transformation into more stable phases like Mg<small>₃</small>(PO<small>₄</small>)<small>₂</small>·8H<small>₂</small>O, resulting in the most severe corrosion degree among all morphologies in the alkaline environment. This work elucidates the crystal-facet-dependent anisotropic corrosion mechanism of struvite, providing a crucial theoretical basis for enhancing the long-term alkali durability of MPC.</p>","PeriodicalId":70,"journal":{"name":"CrystEngComm","volume":" 21","pages":" 3321-3330"},"PeriodicalIF":2.6,"publicationDate":"2026-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148141606","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}