Chemphyschem最新文献

{"title":"Front Cover: Influence of Photoemission Geometry on Timing and Efficiency in 4D Ultrafast Electron Microscopy (ChemPhysChem 5/2025)","authors":"Simon A. Willis,&nbsp;David J. Flannigan","doi":"10.1002/cphc.202580501","DOIUrl":"https://doi.org/10.1002/cphc.202580501","url":null,"abstract":"<p><b>The Front Cover</b> shows unconventional photoelectron emission with a train of ultraviolet femtosecond laser pulses in the electron gun of an ultrafast electron microscope. Off-axis photoemission from the aperture surface of the electron gun leads to surprising behavior of the photoelectron collection efficiency and of the statistical temporal spread of the ultrashort electron packets. More information can be found in the Research Article by S. A. Willis and D. J. Flannigan (DOI: 10.1002/cphc.202401032). Illustration by Rick Simonson, Science Lab Studios, Inc.\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure>\u0000 </p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":"26 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cphc.202580501","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143554615","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":"Charge-transfer Adducts vs Iodine(I) Complexes: Dual Role of Halogen Bonding in Reactions of Diiodine with N-donor Bases.","authors":"Amanda Burnell, Maison Hardin, Matthias Zeller, Sergiy V Rosokha","doi":"10.1002/cphc.202500076","DOIUrl":"10.1002/cphc.202500076","url":null,"abstract":"<p><p>The interaction of diiodine with quinuclidine (QN) and 4-dimethylaminopyridine (DMAP) in solutions with 1 : 1 molar ratio of reactants at room temperature produced (in essentially quantitative yields) pure charge-transfer QN⋅I₂ adducts and iodine(I) salt [DMAP-I-DMAP]I₃, respectively. In comparison, the quantitative formation of pure iodine (I) salt [QN-I-QN]I₅ was observed for the room-temperature reactions of QN with a 50 % excess of I₂, and the charge-transfer adducts of I₂ with DMAP (and other pyridines) were formed when reactions were carried out at low temperatures. Computational analysis related the switch from the formation of charge-transfer adducts to iodine(I) complexes in these systems to the strength of the halogen bonding of diiodine to the N-donor bases. It shows that while the halogen-bonded adducts represent critical intermediates in the formation of iodine(I) complexes, exceedingly strong halogen bonding between diiodine and the base prevents any subsequent transformations. In other words, while halogen bonding usually facilitates electron and halogen transfer, the halogen-bonded complexes may serve as \"black holes\" hindering any follow-up processes if this intermolecular interaction is too strong.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202500076"},"PeriodicalIF":2.3,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143540293","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":"Cryo-EM Informed Molecular Dynamics Simulations to Investigate the Disulfide Hydrogel Self-Assembly.","authors":"Yuanming Song, Zhaoxu Li, Justin Mulvey, J Alfredo Freites, Joseph Patterson, Douglas J Tobias","doi":"10.1002/cphc.202401085","DOIUrl":"https://doi.org/10.1002/cphc.202401085","url":null,"abstract":"<p><p>Disulfide hydrogels, derived from cysteine-based redox systems, exhibit active self-assembly properties driven by reversible disulfide bond formation, making them a versatile platform for dynamic material design. Detailed cryogenic electron microscopy (cryo-EM) analysis revealed a consistent fiber diameter of 5.4 nm for individual fibers. Using cryo-EM-informed radial positional restraints, all-atom molecular dynamics (MD) simulations were employed to reproduce fibers with dimensions closely matching experimental observations, validated further through simulated cryo-EM images. The MD simulations revealed that the disulfide gelator (CSSC) predominantly adopts an open conformation, with hydrogen bonds emerging as the key intermolecular force stabilizing the fibers. Notably, intermolecular interactions were found to be higher at 70% conversion to the disulfide gelator compared to 100%, comparable with past unrestrained simulations. Water molecules and solute-water hydrogen bonds are present throughout the fiber, indicating that the fiber remains hydrated. These findings underscore the potential role of the thiol precursor CSH in stabilizing the transient phase and highlight the importance of CSH-CSSC interplay. This study provides novel insights into molecular mechanisms governing self-assembly and offers strategies for designing tunable materials through controlled assembly conditions.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202401085"},"PeriodicalIF":2.3,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143540296","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":"Tunable Dielectric Carbon Materials from Hydrothermally Nanostructured Organic Carbon Sources.","authors":"Andrea C Landázuri, Yuliana Pullas, Luis Miguel Prócel, Darío Niebieskikwiat, Lourdes M Orejuela-Escobar, Marco León, Víctor H Guerrero, Nelson Herrera, Christian Luciani, Julio C Chacón-Torres","doi":"10.1002/cphc.202400711","DOIUrl":"10.1002/cphc.202400711","url":null,"abstract":"<p><p>This work presents a systematic study of the electronic response and physico-chemical characteristics from hydrothermally treated organic carbon sources (banana peels and cocoa husks). Both samples are exposed to 150 °C and 210 °C for 2, 4, and 6 hours. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and conductivity measurements are used to describe the electronic properties for each organic carbon source. A multicategorical statistical optimization model let us to identify the best dielectric performance considering: a) temperature treatment, b) exposure time, c) frequency, and d) the organic carbon source. Our results indicate that cocoa husk hydrothermally treated samples (CHH) exhibited the best dielectric response, originating from high carboxyl concentrations or diamond-like carbon structures at 150 °C for 6 and 2 hours. In contrast, banana peel hydrothermally treated samples (BPH) are good conductors in comparison to CHH, due to low carboxylation or highly graphitization. This study provides valuable insights into the fundamental structure of lignocellulosic carbon sources that can aid in the development of energy storage and microwave technologies by transforming agricultural residues into high-value electronic materials.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400711"},"PeriodicalIF":2.3,"publicationDate":"2025-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536770","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":"Bond Alternation and Bond Equalization in Linear and Cyclic Conjugated Hydrocarbons: Compared Roles of Sigma and pi Binding using Orbital Forces.","authors":"Patrick Chaquin, François Volatron","doi":"10.1002/cphc.202500045","DOIUrl":"10.1002/cphc.202500045","url":null,"abstract":"<p><p>The phenomena of bond alternation and bond equalisation in conjugated hydrocarbons are studied using dynamic orbital forces (DOF) which provide an index of intrinsic CC binding, with its sigma and pi components. Some linear polyenes, polyynes and cumulenes have been analysed. Dealing with linear polyenes and polyynes, it is shown that sigma bonds can be considered as weak \"inverted\" ones in formally multiple bonds and strong \"superdirect\" ones in formally single ones. This alternance in sigma bonding partly compensates and, in some cases, overcome the alternance in pi binding. Moreover, it was shown from a panel of seven aromatic annulenes and allyl compounds that the bond equalization is favoured by sigma bonding. It can be unfavoured or favoured by the pi binding according to the system and the nature of its deformation into a bond alternant structure.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202500045"},"PeriodicalIF":2.3,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143522682","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":"Discriminating High from Low Energy Conformers of Druglike Molecules: An Assessment of Machine Learning Potentials and Quantum Chemical Methods.","authors":"Linghan Kong, Richard A Bryce","doi":"10.1002/cphc.202400992","DOIUrl":"https://doi.org/10.1002/cphc.202400992","url":null,"abstract":"<p><p>Accurate and efficient prediction of high energy ligand conformations is important in structure-based drug discovery for the exclusion of unrealistic structures in docking-based virtual screening and de novo design approaches. In this work, we constructed a database of 140 solution conformers from 20 druglike molecules of varying size and chemical complexity, with energetics evaluated at the DLPNO-CCSD(T)/complete basis set (CBS) level. We then assessed a selection of machine learning potentials and semiempirical quantum mechanical models for their ability to predict conformational energetics. The GFN2-xTB tight binding density functional method correlates with reference conformer energies, yielding a Kendall's τ of 0.63 and mean absolute error of 2.2 kcal/mol. As putative internal energy filters for screening, we find that the GFN2-xTB, ANI-2x and MACE-OFF23(L) models perform well in identifying low energy conformer geometries, with sensitivities of 95 %, 89 % and 95 % respectively, but display a reduced ability to exclude high energy conformers, with respective specificities of 80 %, 61 % and 63 %. The GFN2-xTB method therefore exhibited the best overall performance and appears currently the most suitable of the three methods to act as an internal energy filter for integration into drug discovery workflows. Enrichment of high energy conformers in the training of machine learning potentials could improve their performance as conformational filters.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400992"},"PeriodicalIF":2.3,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143522741","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":"Spherical Nucleic Acids Meet Acoustic Levitation: A Breakthrough in Synthesis and Application.","authors":"Leiming Chu, Ning Li, Heng Gao, Shixuan Yang, Guangping Li, Honglin Liu","doi":"10.1002/cphc.202401008","DOIUrl":"10.1002/cphc.202401008","url":null,"abstract":"<p><p>Spherical nucleic acids (SNAs), with their densely packed nucleic acid shells and programmable functionalities, have become indispensable in nanomedicine and biosensing. Developed synthesis methods, including salt aging, pH modulation, freeze-thaw cycling, n-butanol dehydration, evaporation drying, and microwave heating, have enabled foundational advances but are constrained by slow kinetics, compromised structural uniformity and especially harsh reaction conditions, making them unsuitable for in situ tracking of biological events. This concept article introduces acoustic levitation synthesis as a groundbreaking alternative, uniquely addressing these limitations through a rapid, green, and highly controllable process. By leveraging non-contact acoustic radiation forces, this method enables the synthesis of ultrahigh-density SNAs within minutes under ambient conditions, eliminating the need for toxic reagents or energy-intensive steps. The resulting SNAs exhibit superior homogeneity and stability compared to conventional approaches. We critically evaluate the conceptual novelty and limitations of this technique. Potential applications in surface-enhanced Raman spectroscopy (SERS) and targeted therapeutics are highlighted, positioning acoustic levitation as a transformative tool for next-generation nanobiotechnology.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202401008"},"PeriodicalIF":2.3,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143499444","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":"Interatomic Interactions and Ion-Transport in a Polyoligomeric Silsesquioxane-Based Multi-Ionic Salt Electrolyte for Lithium-Ion Batteries.","authors":"Shylendran Ardhra, Prabhat Prakash, Rabin Siva Dev, Stephanie L Wunder, Arun Venkatnathan","doi":"10.1002/cphc.202400983","DOIUrl":"10.1002/cphc.202400983","url":null,"abstract":"<p><p>Polyoligomeric silsesquioxane (POSS) tailored with trifluoromethanesulfonylimide-lithium and solvated in tetraglyme (G4) is a potential electrolyte for Li-ion batteries. Using classical MD simulations, at different G4/POSS(-LiNSO₂CF₃)₈ molar ratios, the interactions of Li⁺ ions with the oxygen atoms of G4 and, oxygen/nitrogen sites of the pendant tails, the behaviour of POSS(-^-NSO₂CF₃)₈, and the mobility of species are investigated. The RDFs showed that there exist competing interactions of the O(G4), O(POSS), and N(POSS) sites with Li⁺ ions. The lifetime analysis indicated that Li⁺- - -O(POSS) and Li⁺- - -N(POSS) interactions are longer-lived compared to Li⁺- - -O(G4). The morphological changes of the POSS tails upon interaction with Li⁺ ions were analysed using rotational lifetimes, coiling, and end-to-end distances. The ion-speciation analysis indicated the presence of solvent-separated ion pairs (SSIPs), contact ion pairs (CIPs), and higher-order ion clusters, with SSIPs being the more dominant species at 32/1. The self-diffusion coefficients for the 32/1 system, which showed the least cation-anion interaction, followed the trend: <math> <semantics> <mrow><msub><mi>D</mi> <mrow><mi>G</mi> <mn>4</mn></mrow> </msub> <mo>></mo> <msub><mi>D</mi> <mrow><mi>L</mi> <mi>i</mi> <mo>+</mo></mrow> </msub> <mo>></mo> <msub><mi>D</mi> <mrow><mi>F</mi> <mfenced><mi>P</mi> <mi>O</mi> <mi>S</mi> <mi>S</mi></mfenced> </mrow> </msub> <mo>></mo> <msub><mi>D</mi> <mrow><mi>P</mi> <mi>O</mi> <mi>S</mi> <mi>S</mi></mrow> </msub> </mrow> <annotation>${{D}_{G4}char62 {D}_{Li+}char62 {D}_{Fleft(POSSright)}char62 {D}_{POSS}}$</annotation> </semantics> </math> . The computed cationic transference number (t₊) using the <math> <semantics><msub><mi>D</mi> <mrow><mi>F</mi> <mfenced><mi>P</mi> <mi>O</mi> <mi>S</mi> <mi>S</mi></mfenced> </mrow> </msub> <annotation>${{D}_{Fleft(POSSright)}}$</annotation> </semantics> </math> is consistent with NMR experimental data. The t₊ (and the trends with temperature) computed using the <math> <semantics><msub><mi>D</mi> <mrow><mi>P</mi> <mi>O</mi> <mi>S</mi> <mi>S</mi></mrow> </msub> <annotation>${{D}_{POSS}}$</annotation> </semantics> </math> and ionic conductivities are in good agreement.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400983"},"PeriodicalIF":2.3,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143499443","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":"Identification of Adsorption Sites for CO₂ in a Series of Rare-Earth and Zr-Based Metal-Organic Frameworks.","authors":"Dylan Tassé, Victor Quezada-Novoa, Christopher Copeman, Ashlee J Howarth, Alain Rochefort","doi":"10.1002/cphc.202401050","DOIUrl":"10.1002/cphc.202401050","url":null,"abstract":"<p><p>The adsorption of <math> <semantics><msub><mi>CO</mi> <mn>2</mn></msub> <annotation>${{rm{CO}}_2 }$</annotation> </semantics> </math> in MOF-808, NU-1000 and a series of rare-earth CU-10 analogues has been studied with first principles DFT and classical Monte-Carlo methods. DFT calculations describe the interaction of <math> <semantics><msub><mi>CO</mi> <mn>2</mn></msub> <annotation>${{rm{CO}}_2 }$</annotation> </semantics> </math> with the different metal-organic frameworks (MOFs) as physisorption, but where we can distinguish several adsorption sites in the vicinity of the metal nodes. Beyond the identification of adsorption sites, the MOFs were synthesized, activated, and characterized to evaluate their experimental <math> <semantics><msub><mi>N</mi> <mn>2</mn></msub> <annotation>${{rm{N}}_2 }$</annotation> </semantics> </math> and <math> <semantics><msub><mi>CO</mi> <mn>2</mn></msub> <annotation>${{rm{CO}}_2 }$</annotation> </semantics> </math> adsorption capacity. Classical Grand Canonical Monte-Carlo (GCMC) simulations for the adsorption of <math> <semantics><msub><mi>CO</mi> <mn>2</mn></msub> <annotation>${{rm{CO}}_2 }$</annotation> </semantics> </math> are in very good agreement with DFT results for identifying the most favored adsorption sites in the MOFs. In contrast, a rather mixed agreement between GCMC simulations and experimental results is found for the estimation of adsorption capacity of several MOFs studied toward <math> <semantics><msub><mi>N</mi> <mn>2</mn></msub> <annotation>${{rm{N}}_2 }$</annotation> </semantics> </math> and <math> <semantics><msub><mi>CO</mi> <mn>2</mn></msub> <annotation>${{rm{CO}}_2 }$</annotation> </semantics> </math> .</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202401050"},"PeriodicalIF":2.3,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143490985","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":"Single Atom Sites in Ga-Ni Supported Catalytically Active Liquid Metal Solutions (SCALMS) for Selective Ethylene Oligomerization.","authors":"Alexander Søgaard, Tzung-En Hsieh, Julien Steffen, Simon Carl, Mingjian Wu, Yousuf R Ramzi, Sven Maisel, Johannes Will, Anna Efimenko, Mihaela Gorgoi, Regan G Wilks, Johannes Frisch, Nicola Taccardi, Marco Haumann, Erdmann Spiecker, Andreas Görling, Marcus Bär, Peter Wasserscheid","doi":"10.1002/cphc.202400651","DOIUrl":"10.1002/cphc.202400651","url":null,"abstract":"<p><p>Supported catalytically active liquid metal solutions (SCALMS) are materials composed of a liquid metal alloy deposited on a porous support. Due to the dynamic properties of the liquid metal alloy, these systems are suggested to form single atom sites, resulting in unique catalytic properties. Ga-Ni SCALMS were successfully applied to ethylene oligomerization, yielding catalysts that were stable up to 120 h time on stream. A workflow based on synchrotron-based X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) as well as density function theory (DFT) and ab initio molecular dynamics (AIMD) simulations was applied to investigate the nature of the active species in these materials. The combination of XPS with DFT calculations indeed indicates the presence of isolated single Ni atoms on the liquid metal surface, while TEM measurements show high dynamics in the liquid metal with intermetallic phase dissolution and transformation. Furthermore, DFT/AIMD methods allowed for rationalizing the role of hydrogen pretreatment in enriching the Ni atom at the surface of the liquid metal alloy.</p>","PeriodicalId":9819,"journal":{"name":"Chemphyschem","volume":" ","pages":"e202400651"},"PeriodicalIF":2.3,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143490991","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}