Janardhanan Aswathi, Babu Ann Aleena, Deepa Janardanan
Aminopropanamide (APA), a diamine oxidation product, can contribute significantly to new particle formation (NPF) in the atmosphere by clustering with sulfuric acid (H2SO4) molecules. The presence of amine and the amide functional groups in APA allows for higher H-bonding interaction as well as proton transfer events, which increases the stability of the clusters generated during the early stages of nucleation. Herein, we investigate the contribution of APA to NPF events by means of kinetic simulations and electronic structure calculations at the M062X / 6-311++ G (3df, 3pd) level of theory. It is found that a ppt-level concentration of APA has a higher NPF potential than that of methylamine (MA). Furthermore, at APA concentrations above 10 ppt, its enhancement potential is comparable to that of dimethylamine (DMA). The study further shows that, unlike propenamide (PA), which is effective in NPF only at ppb levels, APA enhances the rate of NPF even at low concentrations of ~ 1 to 25 ppt, comparable to top enhancers such as MA. The presence of the –NH2 group that increases basicity and strengthens the hydrogen bonding interactions stabilizing initial clusters accounts for the unexpectedly high enhancement potential of APA compared to that of PA. Analysis of the effect of temperature on NPF reveals that at low temperatures and at an ambient APA concentration of 25 ppt, the formation rate becomes independent at high SA concentrations, indicating saturation. Additionally, the cluster formation rate is found to be sensitive to the relative humidity of the atmosphere. The NPF rate increases steadily with an increase in humidity until 20%, showing minimal variations thereafter. Our findings highlight the importance of the hitherto unexplored role of aminoamides, such as APA, in nucleation, suggesting that they can emerge as potential base precursors for NPF, especially in regions where it can be formed readily.
氨丙酰胺（APA）是一种二胺氧化产物，通过与硫酸（H2SO4）分子聚类，在大气中形成新粒子（NPF）。APA中胺和酰胺官能团的存在允许更高的h键相互作用以及质子转移事件，这增加了在成核早期阶段产生的团簇的稳定性。本文通过M062X / 6-311++ G （3df, 3pd）理论水平的动力学模拟和电子结构计算，研究了APA对NPF事件的贡献。研究发现，在pt水平浓度下，APA具有比甲胺（MA）更高的NPF电位。此外，当APA浓度超过10 ppt时，其增强潜力与二甲胺（DMA）相当。该研究进一步表明，与丙烯酰胺（PA）不同，丙烯酰胺（PA）仅在ppb水平下对NPF有效，APA即使在~ 1至25 ppt的低浓度下也能提高NPF的速率，与MA等顶级增强剂相当。与PA相比，-NH2基团的存在增加了碱度，加强了氢键相互作用，稳定了初始簇，这是APA具有意想不到的高增强潜力的原因。温度对NPF的影响分析表明，在低温和环境APA浓度为25 ppt时，形成速率在高SA浓度下变得独立，表明饱和。此外，发现星团的形成速率对大气的相对湿度很敏感。NPF率随着湿度的增加而稳步增加，直到20%，此后变化很小。我们的研究结果强调了迄今为止未被探索的氨基酰胺（如APA）在成核中的重要性，表明它们可以作为NPF的潜在碱基前体出现，特别是在易于形成NPF的区域。
{"title":"Enhancement of Sulphuric Acid Based New Particle Formation by 3-Aminopropanamide: Mechanistic, Thermodynamic, and Kinetic Insights","authors":"Janardhanan Aswathi, Babu Ann Aleena, Deepa Janardanan","doi":"10.1039/d5cp03984c","DOIUrl":"https://doi.org/10.1039/d5cp03984c","url":null,"abstract":"Aminopropanamide (APA), a diamine oxidation product, can contribute significantly to new particle formation (NPF) in the atmosphere by clustering with sulfuric acid (H2SO4) molecules. The presence of amine and the amide functional groups in APA allows for higher H-bonding interaction as well as proton transfer events, which increases the stability of the clusters generated during the early stages of nucleation. Herein, we investigate the contribution of APA to NPF events by means of kinetic simulations and electronic structure calculations at the M062X / 6-311++ G (3df, 3pd) level of theory. It is found that a ppt-level concentration of APA has a higher NPF potential than that of methylamine (MA). Furthermore, at APA concentrations above 10 ppt, its enhancement potential is comparable to that of dimethylamine (DMA). The study further shows that, unlike propenamide (PA), which is effective in NPF only at ppb levels, APA enhances the rate of NPF even at low concentrations of ~ 1 to 25 ppt, comparable to top enhancers such as MA. The presence of the –NH2 group that increases basicity and strengthens the hydrogen bonding interactions stabilizing initial clusters accounts for the unexpectedly high enhancement potential of APA compared to that of PA. Analysis of the effect of temperature on NPF reveals that at low temperatures and at an ambient APA concentration of 25 ppt, the formation rate becomes independent at high SA concentrations, indicating saturation. Additionally, the cluster formation rate is found to be sensitive to the relative humidity of the atmosphere. The NPF rate increases steadily with an increase in humidity until 20%, showing minimal variations thereafter. Our findings highlight the importance of the hitherto unexplored role of aminoamides, such as APA, in nucleation, suggesting that they can emerge as potential base precursors for NPF, especially in regions where it can be formed readily.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"44 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146102033","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}
Self-assembling molecules, which form ordered thin films on substrates, and are offered a novel strategy for the development of high-performance perovskite solar cells (PSCs). However, the enhancement of hole transport and interface defect passivation in self-assembled monolayers (SAM)-based materials remain challenging. In this work, we designed three fluorinated isomeric SAM molecules (ZY4, ZY5, ZY6) based on the 4PACz core unit. A combination of density functional theory (DFT), time-dependent DFT (TD-DFT), and molecular dynamics (MD) simulations was employed to investigate the properties, including photoelectronic characteristics, excited-state properties, stability, solubility, and hole transport. Furthermore, theoretical calculations revealed that three SAM molecules exhibit higher dipole moments (3.50 D, 2.81 D, and 2.95D, respectively) than the reference molecule (4-(9H-carbazol-9-yl)butyl) phosphonic acid (1.93 D). Their HOMO energy levels are close to the valence band maximum (VBM) of perovskite, while their LUMO levels lie above the conduction band minimum (CBM). Additionally, they demonstrate more negative solvation free energies compared to that of 4PACz (-0.46 eV). Among them, ZY4 exhibited the highest hole mobility of 6.71×10⁻¹ cm² V⁻¹ s⁻¹. Moreover, the fluorine atoms can form coordination bonds with the Pb²⁺ ions on the perovskite surface. This study demonstrates that the isomerization of fluorinated substituents in 4PACz-core-based SAMs is an effective strategy for enhancing hole transport mobility and optimizing interfacial properties.
{"title":"A Positional Isomerism Strategy of Fluorophenyl Substituents in Self-Assembled Monolayers for Perovskite Solar Cells","authors":"Xing Liu, Hang Deng, Xiaorui Liu","doi":"10.1039/d5cp04902d","DOIUrl":"https://doi.org/10.1039/d5cp04902d","url":null,"abstract":"Self-assembling molecules, which form ordered thin films on substrates, and are offered a novel strategy for the development of high-performance perovskite solar cells (PSCs). However, the enhancement of hole transport and interface defect passivation in self-assembled monolayers (SAM)-based materials remain challenging. In this work, we designed three fluorinated isomeric SAM molecules (ZY4, ZY5, ZY6) based on the 4PACz core unit. A combination of density functional theory (DFT), time-dependent DFT (TD-DFT), and molecular dynamics (MD) simulations was employed to investigate the properties, including photoelectronic characteristics, excited-state properties, stability, solubility, and hole transport. Furthermore, theoretical calculations revealed that three SAM molecules exhibit higher dipole moments (3.50 D, 2.81 D, and 2.95D, respectively) than the reference molecule (4-(9H-carbazol-9-yl)butyl) phosphonic acid (1.93 D). Their HOMO energy levels are close to the valence band maximum (VBM) of perovskite, while their LUMO levels lie above the conduction band minimum (CBM). Additionally, they demonstrate more negative solvation free energies compared to that of 4PACz (-0.46 eV). Among them, ZY4 exhibited the highest hole mobility of 6.71×10⁻¹ cm² V⁻¹ s⁻¹. Moreover, the fluorine atoms can form coordination bonds with the Pb²⁺ ions on the perovskite surface. This study demonstrates that the isomerization of fluorinated substituents in 4PACz-core-based SAMs is an effective strategy for enhancing hole transport mobility and optimizing interfacial properties.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"275 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146102035","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}
Joni Eronen, Perttu Hilla, Vladimir V. Zhivonitko, Juha Vaara, Anu Maria Kantola
Signal amplification by reversible exchange (SABRE) is a parahydrogen-based hyperpolarisation technique that significantly enhances nuclear magnetic resonance signals without expensive hardware. While conventional SABRE relies on a static polarisation transfer field set near the level anticrossing (LAC) condition, recent work has shown that oscillating fields can substantially boost the hyperpolarisation levels. Here, we develop a new theoretical model that generalises the LAC condition to account for the oscillating polarisation transfer fields, thereby explaining the spin dynamics of SABRE under such conditions. We demonstrate that the oscillating fields can be used to optimise coherent polarisation transfer while simultaneously suppressing scalar relaxation of the second kind. Large-scale spin dynamics simulations and experiments show enhanced 19F hyperpolarisation compared to conventional SABRE, with a 79% improvement observed experimentally. This work demonstrates a generalisable strategy for improving the efficiency of SABRE, advancing its potential for various applications, such as in biomedicine.
{"title":"Generalised level anticrossings explain improved 19F SABRE hyperpolarisation under oscillating magnetic fields","authors":"Joni Eronen, Perttu Hilla, Vladimir V. Zhivonitko, Juha Vaara, Anu Maria Kantola","doi":"10.1039/d5cp04781a","DOIUrl":"https://doi.org/10.1039/d5cp04781a","url":null,"abstract":"Signal amplification by reversible exchange (SABRE) is a parahydrogen-based hyperpolarisation technique that significantly enhances nuclear magnetic resonance signals without expensive hardware. While conventional SABRE relies on a static polarisation transfer field set near the level anticrossing (LAC) condition, recent work has shown that oscillating fields can substantially boost the hyperpolarisation levels. Here, we develop a new theoretical model that generalises the LAC condition to account for the oscillating polarisation transfer fields, thereby explaining the spin dynamics of SABRE under such conditions. We demonstrate that the oscillating fields can be used to optimise coherent polarisation transfer while simultaneously suppressing scalar relaxation of the second kind. Large-scale spin dynamics simulations and experiments show enhanced <small><sup>19</sup></small>F hyperpolarisation compared to conventional SABRE, with a 79% improvement observed experimentally. This work demonstrates a generalisable strategy for improving the efficiency of SABRE, advancing its potential for various applications, such as in biomedicine.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"8 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146102031","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}
The widespread application of metal-organic frameworks (MOFs) is hindered by their hydrolytic instability in aqueous and humid environments. To overcome this bottleneck, herein, we evaluate four representative MOFs– MOF-303 (highly stable), MIL-127(Fe) (stable), HKUST-1 (moderately unstable), and UMCM-1 (unstable)– using periodic and fragment-based density functional theory. By distinguishing the water adsorption, condensation, and hydrolysis pathways, we identify the structural and chemical factors that govern stability. Our results reveal the dual impact of water: it can destabilize frameworks by facilitating metal–ligand bond cleavage and improving ligand-ligand interactions of detached linkers, as in UMCM-1 and HKUST-1, but can also enhance stability by forming extended hydrogen-bond networks with polar ligands, as observed in MOF-303. This cooperative water–ligand interaction shields metal–oxygen bonds and prevents pore collapse, challenging the prevailing view that hydrophobicity is a key to promoting stability. These insights clarify contradictory experimental reports and establish general design principles, highlighting that water is both a threat and a stabilizer depending on the framework’s connectivity and ligand chemistry.
{"title":"Dual impact of water on stability of metal-organic frameworks","authors":"Fatemeh Keshavarz","doi":"10.1039/d5cp04782j","DOIUrl":"https://doi.org/10.1039/d5cp04782j","url":null,"abstract":"The widespread application of metal-organic frameworks (MOFs) is hindered by their hydrolytic instability in aqueous and humid environments. To overcome this bottleneck, herein, we evaluate four representative MOFs– MOF-303 (highly stable), MIL-127(Fe) (stable), HKUST-1 (moderately unstable), and UMCM-1 (unstable)– using periodic and fragment-based density functional theory. By distinguishing the water adsorption, condensation, and hydrolysis pathways, we identify the structural and chemical factors that govern stability. Our results reveal the dual impact of water: it can destabilize frameworks by facilitating metal–ligand bond cleavage and improving ligand-ligand interactions of detached linkers, as in UMCM-1 and HKUST-1, but can also enhance stability by forming extended hydrogen-bond networks with polar ligands, as observed in MOF-303. This cooperative water–ligand interaction shields metal–oxygen bonds and prevents pore collapse, challenging the prevailing view that hydrophobicity is a key to promoting stability. These insights clarify contradictory experimental reports and establish general design principles, highlighting that water is both a threat and a stabilizer depending on the framework’s connectivity and ligand chemistry.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"233 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146102032","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}
Shijie Guo, Kai Cheng, Guotai Zhang, Peng Wu, Jianpei Xing, Sandong Guo, Yan Su
Using high-throughput GGA+U first-principles calculations we survey the formation energy, magnetic ground state and spin-valley-coupled electronic structure of 87 monolayer 2H-phase MX2 (M = Groups-IIIB-IIB, X = S, Se, Te). A systematic group-by-group evolution is uncovered: 3d-based TMDs favor antiferromagnetic (AFM) semiconductors, 4d congeners stabilize ferromagnetic (FM) metals or bipolar magnetic semiconductors (BMSs), whereas 5d members are overwhelmingly non-magnetic metals. Thermodynamic stability (ΔHf ≤ 0) is fulfilled for all sulfides/selenides/tellurides of Groups-IIIB-VIB and most of Groups-VIIB-VIII, whereas post-transition-metal TMDs (Groups IB-IIB) are unstable. Valley polarization is dictated by the interplay between hexagonal lattice symmetry and magnetic order: FM Group-VB VX2 and BMS VSe2/VTe2 exhibit 100% spin-polarized K/K' band edges ideal for the anomalous valley Hall effect, while AFM Group-VIB CrX2 and Mo/WX2 retain spin-degenerate K-point valleys suitable for reversible valleytronics. The resulting atlas provides an experimentally verifiable blueprint for wafer-scale synthesis of high-temperature FM, half-metallic or valley-polarized 2D crystals and accelerates the materialization of next-generation spin-valleytronic devices.
利用高通量GGA+U第一性原理计算，研究了87种单层2h相MX2 （M = group - iiib - iib, X = S, Se, Te）的形成能、磁基态和自旋谷耦合电子结构。研究揭示了一种系统的逐群演化：基于3d的tmd倾向于反铁磁（AFM）半导体，基于4d的tmd倾向于稳定铁磁（FM）金属或双极磁性半导体（bms），而基于5d的tmd成员绝大多数是非磁性金属。所有- iib - vib族的硫化物/硒化物/碲化物和大部分- vib - viii族的硫化物/硒化物/碲化物均满足热力学稳定性（ΔHf≤0），而过渡后金属TMDs （IB-IIB族）则不稳定。谷极化是由六方晶格对称和磁序之间的相互作用决定的：FM Group-VB VX2和BMS VSe2/VTe2表现出100%自旋极化的K/K'带边缘，非常适合反常谷霍尔效应，而AFM Group-VIB CrX2和Mo/WX2保留了适合可逆谷电子的自旋简并K点谷。由此产生的图谱为高温调频、半金属或谷偏振二维晶体的晶圆级合成提供了实验验证的蓝图，并加速了下一代自旋谷电子器件的物化。
{"title":"First-principles decoding of spin-valley-polarized H-phase TMDs: formation energies, magnetic ground states, and band engineering.","authors":"Shijie Guo, Kai Cheng, Guotai Zhang, Peng Wu, Jianpei Xing, Sandong Guo, Yan Su","doi":"10.1039/d5cp04973c","DOIUrl":"https://doi.org/10.1039/d5cp04973c","url":null,"abstract":"<p><p>Using high-throughput GGA+<i>U</i> first-principles calculations we survey the formation energy, magnetic ground state and spin-valley-coupled electronic structure of 87 monolayer 2H-phase MX<sub>2</sub> (M = Groups-IIIB-IIB, X = S, Se, Te). A systematic group-by-group evolution is uncovered: 3d-based TMDs favor antiferromagnetic (AFM) semiconductors, 4d congeners stabilize ferromagnetic (FM) metals or bipolar magnetic semiconductors (BMSs), whereas 5d members are overwhelmingly non-magnetic metals. Thermodynamic stability (Δ<i>H</i><sub>f</sub> ≤ 0) is fulfilled for all sulfides/selenides/tellurides of Groups-IIIB-VIB and most of Groups-VIIB-VIII, whereas post-transition-metal TMDs (Groups IB-IIB) are unstable. Valley polarization is dictated by the interplay between hexagonal lattice symmetry and magnetic order: FM Group-VB VX<sub>2</sub> and BMS VSe<sub>2</sub>/VTe<sub>2</sub> exhibit 100% spin-polarized K/K' band edges ideal for the anomalous valley Hall effect, while AFM Group-VIB CrX<sub>2</sub> and Mo/WX<sub>2</sub> retain spin-degenerate K-point valleys suitable for reversible valleytronics. The resulting atlas provides an experimentally verifiable blueprint for wafer-scale synthesis of high-temperature FM, half-metallic or valley-polarized 2D crystals and accelerates the materialization of next-generation spin-valleytronic devices.</p>","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146103210","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}
Heteronuclear alkali diatomics in the lowest triplet state possess electric and magnetic dipoles, making them promising for quantum simulation of many-body physics. However, an analytical formula with physical transparency to describe the interaction potential of the heteronuclear alkali dimers involving Li atom is still lacking. The present article shows that the Sheng-Tang-Toennies (STT) potential model with only two adjustable parameters describes the full-range potential energy curve (PEC) of the LiNa molecule in its lowest triplet electronic state (a 3 + u ) with high accuracy. Validation against high-accuracy ab initio data and experimental spectroscopy demonstrates exceptional agreement across all internuclear distances, with deviations < 1% from ab initio calculations and Rydberg-Klein-Rees (RKR) potentials. The model achieves high-precision predictions for: vibrational energy levels show a root-mean-square error (RMSE) of 0.1965 cm -1 (11 observed states), and the s-wave scattering length is calculated as -71.28 a.u., consistent with experimental bounds (-76 ± 5 a.u.).This work demonstrate the STT model is efficacy for modeling the PEC of heteronuclear alkali dimers involving Li atom.
处于最低三重态的异核碱双原子具有电偶极子和磁偶极子，在多体物理的量子模拟中具有广阔的应用前景。然而，目前还缺乏一个具有物理透明性的解析公式来描述含有Li原子的异核碱二聚体的相互作用势。本文表明，仅含两个可调参数的生-唐-托尼斯（STT）势模型可以高精度地描述LiNa分子在最低三态电子态（a3 + u）下的全范围势能曲线（PEC）。对高精度从头算数据和实验光谱的验证表明，在所有核间距离上都非常一致，与从头算计算和Rydberg-Klein-Rees （RKR）势的偏差为1%。该模型实现了高精度的预测：振动能级的均方根误差（RMSE）为0.1965 cm -1（11个观测状态），s波散射长度计算为-71.28 a.u，与实验界（-76±5 a.u）一致。本文的工作证明了STT模型对于模拟含Li原子的异核碱二聚体的PEC是有效的。
{"title":"Full-Range Analytical Potential for the a Σ3+u State of LiNa: Robust Prediction of Vibrational Levels and Scattering Length","authors":"Dongying Li, Xiaowei Sheng","doi":"10.1039/d5cp04966k","DOIUrl":"https://doi.org/10.1039/d5cp04966k","url":null,"abstract":"Heteronuclear alkali diatomics in the lowest triplet state possess electric and magnetic dipoles, making them promising for quantum simulation of many-body physics. However, an analytical formula with physical transparency to describe the interaction potential of the heteronuclear alkali dimers involving Li atom is still lacking. The present article shows that the Sheng-Tang-Toennies (STT) potential model with only two adjustable parameters describes the full-range potential energy curve (PEC) of the LiNa molecule in its lowest triplet electronic state (a 3 + u ) with high accuracy. Validation against high-accuracy ab initio data and experimental spectroscopy demonstrates exceptional agreement across all internuclear distances, with deviations < 1% from ab initio calculations and Rydberg-Klein-Rees (RKR) potentials. The model achieves high-precision predictions for: vibrational energy levels show a root-mean-square error (RMSE) of 0.1965 cm -1 (11 observed states), and the s-wave scattering length is calculated as -71.28 a.u., consistent with experimental bounds (-76 ± 5 a.u.).This work demonstrate the STT model is efficacy for modeling the PEC of heteronuclear alkali dimers involving Li atom.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"61 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146098375","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}
Decheng Peng, Xin Li, LiangFu Zhao, Jiangang Chen, Qiang Wang
Single-atom catalysts have been widely used for electro-reduction CO2 (CO2RR). In this study, density functional theory is employed to evaluate the electrocatalytic performance of pyridine-based graphyne anchoring with second-row transition metal atom (TM-pdGY) towards CO2RR. The most stable configuration and corresponding structural attribute were obtained by structure optimization. Then, the energy calculation results related to the structure show large bonding energies (-0.82 to -5.92 eV), comparatively higher cohesive energies (-0.7 to -7.6 eV per atom) and moderate formation energy (-1.63 to 2.65 eV) which indicates the structural stability and preparation feasibility. The results of electronic structure analysis also prove the existence of firm covalent bonds by revealing the frequent charge transfer and significant orbital hybridization between metal atoms and the catalyst substrate. The competitive analysis between CO2RR and hydrogen evolution reaction show that all TM-pdGYs have a higher selectivity for CO2RR. Through Gibbs free energy graphs and reaction pathway diagram of four C1 products, the most favorable products (CH4 and HCOOH) of TM-pdGYs have been determined. It is demonstrated that the regulation of the overall electronic structure of the catalyst by the TM-N coordination structure is the origin of the high CO₂RR activity. It is worth noting that Ru/Rh/Pd/Cd-pdGYs possess higher CO2RR activity because of their lower limiting potentials (UL) (-0.51 to -0.88 V). These results indicate that the second-row TM-pdGYs exhibit excellent performance for CO2RR.
{"title":"Insights into pyridine-based graphynes anchoring with second-row transition metal single atoms for electrocatalytic CO2 reduction: a DFT study","authors":"Decheng Peng, Xin Li, LiangFu Zhao, Jiangang Chen, Qiang Wang","doi":"10.1039/d5cp04064g","DOIUrl":"https://doi.org/10.1039/d5cp04064g","url":null,"abstract":"Single-atom catalysts have been widely used for electro-reduction CO2 (CO2RR). In this study, density functional theory is employed to evaluate the electrocatalytic performance of pyridine-based graphyne anchoring with second-row transition metal atom (TM-pdGY) towards CO2RR. The most stable configuration and corresponding structural attribute were obtained by structure optimization. Then, the energy calculation results related to the structure show large bonding energies (-0.82 to -5.92 eV), comparatively higher cohesive energies (-0.7 to -7.6 eV per atom) and moderate formation energy (-1.63 to 2.65 eV) which indicates the structural stability and preparation feasibility. The results of electronic structure analysis also prove the existence of firm covalent bonds by revealing the frequent charge transfer and significant orbital hybridization between metal atoms and the catalyst substrate. The competitive analysis between CO2RR and hydrogen evolution reaction show that all TM-pdGYs have a higher selectivity for CO2RR. Through Gibbs free energy graphs and reaction pathway diagram of four C1 products, the most favorable products (CH4 and HCOOH) of TM-pdGYs have been determined. It is demonstrated that the regulation of the overall electronic structure of the catalyst by the TM-N coordination structure is the origin of the high CO₂RR activity. It is worth noting that Ru/Rh/Pd/Cd-pdGYs possess higher CO2RR activity because of their lower limiting potentials (UL) (-0.51 to -0.88 V). These results indicate that the second-row TM-pdGYs exhibit excellent performance for CO2RR.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"80 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146098376","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}
Yuming Zhao, Nicholas Pengrui Qiu, Liam Harrison Britt, Ramin Eradeh
This study investigates polycyclic aromatic fluorophores featuring pyrene and phenanthrene fused through either an imidazo[1,2-a]azepinone or an imidazo[1,2-a]azepinol central ring. These fluorophores were synthesized via a one-pot pyrene-4,5-dione condensation reaction and a subsequent metal hydride reduction. The molecular structures of two representative fluorophores were unequivocally determined by single-crystal X-ray diffraction (SCXRD) analysis, while their electronic absorption and emission properties were comprehensively characterized using UV-Vis absorption and fluorescence spectroscopy. Excitation-emission matrix (EEM) fluorescence spectroscopy was employed to provide further insight into their emission behavior as a function of excitation energy. A combination of spectroscopic and density functional theory (DFT) studies revealed that the fluorescence behavior of azepinone-centered fluorophores is governed by a planarization-induced intramolecular charge transfer (PLICT) mechanism, resulting in pronounced solvatofluorochromism but relatively low fluorescence quantum yields. In contrast, azepinol-based fluorophores exhibited significantly higher fluorescence efficiency, albeit with much weaker solvatofluorochromic effects. To assess their potential for bioimaging applications, we investigated the interactions of these fluorophores with bovine serum albumin (BSA) as a model protein using fluorescence titration. All fluorophores bound to BSA, quenching its tryptophan fluorescence at 354 nm while emitting at their characteristic wavelengths. Detailed binding parameters were derived by fitting the data to the Stern-Volmer equation and a 1:1 binding isotherm. Molecular docking and molecular dynamics (MD) simulations further elucidated the fluorophore-BSA interactions at the atomic level. Finally, the fluorophores were incubated with two types of bacterial cell to evaluate their fluorescence imagining performance. The results demonstrated promising utility in optical sensing and imaging of bacteria.
{"title":"Fusion of pyrene and phenanthrene through 5H-imidazo[1,2-a]azepine scaffolds: structural tuning for fluorescence labeling and bacterial imaging","authors":"Yuming Zhao, Nicholas Pengrui Qiu, Liam Harrison Britt, Ramin Eradeh","doi":"10.1039/d5cp02942b","DOIUrl":"https://doi.org/10.1039/d5cp02942b","url":null,"abstract":"This study investigates polycyclic aromatic fluorophores featuring pyrene and phenanthrene fused through either an imidazo[1,2-a]azepinone or an imidazo[1,2-a]azepinol central ring. These fluorophores were synthesized via a one-pot pyrene-4,5-dione condensation reaction and a subsequent metal hydride reduction. The molecular structures of two representative fluorophores were unequivocally determined by single-crystal X-ray diffraction (SCXRD) analysis, while their electronic absorption and emission properties were comprehensively characterized using UV-Vis absorption and fluorescence spectroscopy. Excitation-emission matrix (EEM) fluorescence spectroscopy was employed to provide further insight into their emission behavior as a function of excitation energy. A combination of spectroscopic and density functional theory (DFT) studies revealed that the fluorescence behavior of azepinone-centered fluorophores is governed by a planarization-induced intramolecular charge transfer (PLICT) mechanism, resulting in pronounced solvatofluorochromism but relatively low fluorescence quantum yields. In contrast, azepinol-based fluorophores exhibited significantly higher fluorescence efficiency, albeit with much weaker solvatofluorochromic effects. To assess their potential for bioimaging applications, we investigated the interactions of these fluorophores with bovine serum albumin (BSA) as a model protein using fluorescence titration. All fluorophores bound to BSA, quenching its tryptophan fluorescence at 354 nm while emitting at their characteristic wavelengths. Detailed binding parameters were derived by fitting the data to the Stern-Volmer equation and a 1:1 binding isotherm. Molecular docking and molecular dynamics (MD) simulations further elucidated the fluorophore-BSA interactions at the atomic level. Finally, the fluorophores were incubated with two types of bacterial cell to evaluate their fluorescence imagining performance. The results demonstrated promising utility in optical sensing and imaging of bacteria.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"34 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146098372","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}
Oleksandr Korostyshevskyi, Cameron K. Wetzel, David M. Lee, Vladimir V. Khmelenko
We studied the luminescence of neon nanoclusters doped with nitrogen atoms. Neon nanoclusters were collected inside bulk superfluid helium at temperatures below 1.5 K. We found that the spectra of the nitrogen atom α-group had a specific shape with an enhanced narrow line at λ = 519.9 nm. The measured spectroscopic characteristics of this line, such as the position, narrow linewidth, relatively large intensity, and long lifetime, allow assignment of this line to nitrogen atoms on the surfaces of neon nanoclusters, surrounded by layers of solid helium. This is the first observation of the influence of solid helium on the spectral characteristics of atoms inside the bulk superfluid helium.
{"title":"Influence of solid helium on the luminescence of nitrogen–neon nanoclusters","authors":"Oleksandr Korostyshevskyi, Cameron K. Wetzel, David M. Lee, Vladimir V. Khmelenko","doi":"10.1039/d5cp04357c","DOIUrl":"https://doi.org/10.1039/d5cp04357c","url":null,"abstract":"We studied the luminescence of neon nanoclusters doped with nitrogen atoms. Neon nanoclusters were collected inside bulk superfluid helium at temperatures below 1.5 K. We found that the spectra of the nitrogen atom α-group had a specific shape with an enhanced narrow line at <em>λ</em> = 519.9 nm. The measured spectroscopic characteristics of this line, such as the position, narrow linewidth, relatively large intensity, and long lifetime, allow assignment of this line to nitrogen atoms on the surfaces of neon nanoclusters, surrounded by layers of solid helium. This is the first observation of the influence of solid helium on the spectral characteristics of atoms inside the bulk superfluid helium.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"94 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146098400","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}
Guanzhi Wu, Junchi Liu, Yan Xie, Xian-Sheng Ke, Wenkai Zhang
Dibenzo [g,p]chrysene-fused Bis-Dicarbacorrole (Bis-H 3 ) metal complexes show unique electron configurations and properties depends on the number and the type of coordinated metal centers as there are two coordinative adj-CCNN subunits. When Cu(III) ions coordinated in, π electrons in Bis-H 3 ligand maintains and when Pd(II) ions coordinated in, each Pd(II) would induce one π electron from Bis-H 3 ligand donated to the Pd center so the electron configuration and aromaticity of Bis-H 3 ligand could be modified by introducing Pd(II) centers coordinated in. In this research, by applying transient absorption spectroscopy with probe range in both visible range and near infrared range, together with density functional theory and time-dependent density functional theory calculations. It was found that for Bis-H 3 complexes only with Cu(III) centers, ligand-to-metal charge transfer state could be populated after excitation at its Soret-like band but for complexes include Pd(II) metal centre, metal-to-ligand charge transfer state is populated instead and its lifetime is much longer than Cu(III) only Bis-H 3 complex. The Pd(II) included Bis-H 3 complex's charge recombination rate is also found high corresponding with electron hole distance of the excited state populated. For Bis-H 3 metal complexes, photoinduced electron transfer direction and corresponding charge recombination rate could be modified by changing the metal centers coordinated in.
二苯并[g，p]铬熔融双-二甲咯（bis - h3）金属配合物具有独特的电子构型和性质，这取决于配位金属中心的数量和类型，因为有两个配位的adj-CCNN亚基。当Cu（III）离子配位时，铋- h - 3配体的π电子保持不变；当Pd（II）离子配位时，每个Pd（II）离子诱导一个π电子给到铋- h - 3配体的Pd中心，从而通过引入配位的Pd（II）中心来修饰铋- h - 3配体的电子构型和芳构性。在本研究中，采用探测范围为可见光和近红外的瞬态吸收光谱，结合密度泛函理论和时变密度泛函理论进行计算。研究发现，对于仅含Cu（III）中心的铋-氢3配合物，在其soret带激发后会填充配体到金属的电荷转移态，但对于含Pd（II）金属中心的配合物，则会填充金属到配体的电荷转移态，其寿命比仅含Cu（III）的铋-氢3配合物要长得多。含有铋- h3的Pd（II）配合物的电荷复合率也与填充激发态的电子空穴距离相对应。对于bis - h3金属配合物，通过改变配位的金属中心可以改变光致电子转移方向和相应的电荷复合速率。
{"title":"On the Characteristic and Dynamics of Excited States Populated After Excitation at Soret-like Band of Dibenzo[g,p]chrysene-fused Bis-Dicarbacorrole Cu(III) and Pd(II) Metal Complexes","authors":"Guanzhi Wu, Junchi Liu, Yan Xie, Xian-Sheng Ke, Wenkai Zhang","doi":"10.1039/d5cp04061b","DOIUrl":"https://doi.org/10.1039/d5cp04061b","url":null,"abstract":"Dibenzo [g,p]chrysene-fused Bis-Dicarbacorrole (Bis-H 3 ) metal complexes show unique electron configurations and properties depends on the number and the type of coordinated metal centers as there are two coordinative adj-CCNN subunits. When Cu(III) ions coordinated in, π electrons in Bis-H 3 ligand maintains and when Pd(II) ions coordinated in, each Pd(II) would induce one π electron from Bis-H 3 ligand donated to the Pd center so the electron configuration and aromaticity of Bis-H 3 ligand could be modified by introducing Pd(II) centers coordinated in. In this research, by applying transient absorption spectroscopy with probe range in both visible range and near infrared range, together with density functional theory and time-dependent density functional theory calculations. It was found that for Bis-H 3 complexes only with Cu(III) centers, ligand-to-metal charge transfer state could be populated after excitation at its Soret-like band but for complexes include Pd(II) metal centre, metal-to-ligand charge transfer state is populated instead and its lifetime is much longer than Cu(III) only Bis-H 3 complex. The Pd(II) included Bis-H 3 complex's charge recombination rate is also found high corresponding with electron hole distance of the excited state populated. For Bis-H 3 metal complexes, photoinduced electron transfer direction and corresponding charge recombination rate could be modified by changing the metal centers coordinated in.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"41 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146098374","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}
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