Physical Chemistry Chemical Physics最新文献

{"title":"Molecular conformational effects on the overall rate constant and the branching ratios of the n-heptane + OH reaction: An ab initio and variational transition state theory study","authors":"Myriam Belmekki, Manuel Monge Palacios, Tairan Wang, Subram Mani Sarathy","doi":"10.1039/d5cp00301f","DOIUrl":"https://doi.org/10.1039/d5cp00301f","url":null,"abstract":"The oxidation of fuels by hydroxyl radical (OH) is a crucial initiation step in both combustion and atmospheric processes. In the present work, we explore the site-specific hydrogen atom abstraction reactions by OH from <em>n</em>-heptane through high level ab initio and sophisticated kinetic calculations. Rate constants for each of the four distinct abstraction sites were computed, for the first time, over a wide temperature range (200-3000 K) and using multistructural torsional variational transition state theory (MS-T-VTST) with small curvature tunneling (SCT) corrections. Optimized geometries, vibrational frequencies and minimum energy paths (MEPs) were determined using the M06-2X/aug-cc-pVTZ level of theory, with single-point energy refinements performed at the CCSD(T)/aug-cc-pVTZ level of theory to refine the energy of the optimized stationary points whose energy is up to 1 kcal mol<small>^-1</small> of their respective global minimum conformer. Our findings reveal that the overall rate constants obtained from our site-specific calculations align closely with experimental data, with a maximum deviation factor (k<small>^exp</small>/k<small>^theory</small>) of 1.5 at 1000 K. More importantly, we provide branching ratios that are based on first-principle calculations, identifying the secondary site neighboring the primary site as the dominant abstraction channel—data not previously reported in the literature, thereby adding value to our kinetic study. Moreover, we demonstrate that, as long as multi-structural torsional anhamonicity effects are implemented, appropriate density functional methods with large enough basis sets can yield rate constants that are comparable to those from much more computationally demaning levels of theory that are based on wave function methods. The demonstrated protocol, in which we have also tested the effect of different energy cuttoffs for the computationally intensive single-point energy refinements, effectively handles large and conformationally complex chemical systems, offering a reliable framework for future investigations in this field involving similar chemical systems whose kinetics is barely known or simply based on estimations.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"23 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143462602","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":"Towards detection of molecular parity violation via chiral co-sensing: the 1H/31P model system","authors":"Erik Van Dyke, James Eills, Kirill Sheberstov, John Blanchard, Manfred Wagner, Andrés Emilio Wedenig, Konstantin Gaul, Robert Berger, Denis Kargin, Rudolf Pietschnig, Danila A. Barskiy, Dmitry Budker","doi":"10.1039/d5cp00126a","DOIUrl":"https://doi.org/10.1039/d5cp00126a","url":null,"abstract":"Fundamental weak interactions have been shown to violate parity in both nuclear and atomic systems. However, observation of parity violation in a molecular system has proven an elusive target. Nuclear spin dependent contributions of the weak interaction are expected to result in energetic differences between enantiomers manifesting in nuclear magnetic resonance (NMR) spectra as chemical shift differences on the order of parts-per-trillion to parts-per-billion ($upmu$Hz to mHz) for high-$Z$ nuclei. This method seeks to use simultaneous measurements of the diastereomeric splittings for a light and a heavy nucleus in solution-state NMR to resolve chemical shift differences persisting in a non-chiral environment between enantiomers of chiral compounds smaller than the typical high-field NMR linewidth. Sources of error must be identified and minimized to verify that the observed effect is, in fact, due to parity violation and not systematic effects. This paper presents a detailed analysis of a system incorporating $^{31}$P and $^{1}$H NMR to elucidate the systematic effects and to guide experiments with higher-$Z$ nuclei where molecular parity violation may be resolved.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"14 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143462603","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":"Gas-phase, conformer-specific infrared spectra of 3-chlorophenol and 3-fluorophenol","authors":"Olga Anna Duda, Gerrit Groenenboom, Daniel A. Horke, Joost Bakker","doi":"10.1039/d4cp04352a","DOIUrl":"https://doi.org/10.1039/d4cp04352a","url":null,"abstract":"Conformational isomerism of phenol derivatives has been a subject of extensive spectroscopic study. Combining the capabilities of the widely tuneable infrared free-electron laser FELIX with molecular beam technologies allows for revisiting existing data and gaining additional insights into far-IR spectroscopy of halogenated phenols. Here we present conformer-resolved infrared spectra of the syn and anti conformers of 3-chlorophenol and 3-fluorophenol recorded via IR-UV ion-dip spectroscopy. The experimental work is complemented by density functional theory calculations to aid in assignment of the observed bands. The experimental spectra for the two isomers of each molecule show overall a great similarity, but also include some distinct isomer-specific bands in the spectral range investigated. Our spectra confirm previously reported OH torsional mode frequencies for the syn and anti conformers of 3-chlorophenol at 315 cm-1, (Manocha et al. J. Phys. Chem. 77, 2094 (1973)) but reverse their assignment of the 311 and 319 cm-1 bands for 3-fluorophenol. 1D torsional mode calculations were performed for 3CP to help assign possible OH torsion overtones.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"27 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143470460","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":"Expanded ensemble predictions of toluene–water partition coefficients in the SAMPL9 LogP challenge","authors":"Steven Goold, Robert M. Raddi, Vincent Voelz","doi":"10.1039/d4cp03621b","DOIUrl":"https://doi.org/10.1039/d4cp03621b","url":null,"abstract":"The logarithm of the partition coefficient (logP) between water and a nonpolar solvent is useful for characterizing a small molecule's hydrophobicity. For example, the water–octanol logP is often used as a predictor of a drug’s lipophilicity and/or membrane permeability, good indicators of its bioavailability. Existing computational predictors of water–octanol logP are generally very accurate due to the wealth of experimental measurements, but may be less so for other non-polar solvents such as toluene. In this work, we participate in a Statistical Assessment of the Modeling of Proteins and Ligands (SAMPL) logP challenge to examine the accuracy of a molecular simulation-based absolute free energy approach to predict water–toluene logP in a blind test for sixteen drug-like compounds with acid-base properties. Our simulation workflow used the OpenFF 2.0.0 force field, and an expanded ensemble (EE) method for free energy estimation, which enables efficient parallelization over multiple distributed computing clients for enhanced sampling. The EE method uses Wang-Landau flat-histogram sampling to estimate the free energy of decoupling in each solvent, and can be performed in a single simulation. Our protocol also includes a step to optimize the schedule of alchemical intermediates in each decoupling. The results show that our EE workflow is able to accurately predict free energies of transfer, achieving an RMSD of 2.26 kcal/mol, and <em>R</em><small>²</small> of 0.80. An examination of outliers suggests that improved force field parameters could achieve better accuracy. Overall, our results suggest that expanded ensemble free energy calculations provide accurate first-principles logP prediction.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"16 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143462601","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":"High energy electron beam irradiation on the electrolyte enables fast-charging of lithium metal battery with long-term cycling stability","authors":"Miaomiao Yu, Qiaoan Liu, Yuxin Rao, Huasong Wang, Pengfei Liu, Xue Li, Yan Zhang, Shan Fang","doi":"10.1039/d5cp00021a","DOIUrl":"https://doi.org/10.1039/d5cp00021a","url":null,"abstract":"Electron beam (E-beam) irradiation serves as a pivotal tool within the realms of materials science, nanotechnology, and microelectronics. Its application is instrumental in altering the physical and chemical properties of materials, which enabling the exploration of material characteristics and fosters the advent of novel technologies advancements. In this work, to investigate the effect of E-beam irradiation on the electrolyte of lithium-metal batteries, a commercially available carbonate based electrolyte LB-085 was exposed to E-beam irradiation at different doses (10, 25, 50 kGy), significantly alters the chemical composition of the electrolyte and modifies various physical parameters. It effectively mitigates interfacial side reactions that occur during the cycles of an electrode, securing a stable solid state electrolyte interphase (SEI) characterized by high ionic conductivity. This, in turn, facilitates rapid charging performance of the battery. The lithium metal full-cell assembled with LiNi0.91Co0.06Mn0.03O2 (NCM91 ) demonstrates superior capacity retention, exceeded 80% after 450 cycles 4C rate and after 600 cycles at 6C rate with an irradiation dose of 50 kGy on the electrolyte. This research pioneers fresh perspectives for electrolyte optimization, focusing on enhancing the rapid charging performance of batteries.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"1 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143443848","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":"Assessing residual stress generation and entrapment in glass-to-metal seals: Role of glass solidification during the cooling process","authors":"Keqian Gong, Chao Zhou, Zheng Liu, Zifeng Song, Zhangjing Shi, Weisong Zhou, Yong Zhang","doi":"10.1039/d4cp03661a","DOIUrl":"https://doi.org/10.1039/d4cp03661a","url":null,"abstract":"Glass-to-metal (GTM) seals present significant challenges due to residual stress (RS) in engineering applications. While previous studies have focused primarily on analyzing the final RS distribution, this work uniquely explores the formation and entrapment of stress during the cooling process, which has been largely overlooked. By investigating cooling-induced changes in glass properties, it reveals the pivotal role of glass solidification and the intricate interplay between thermal dynamics and mechanical properties in shaping stress distribution within GTM seals. Using a combination of photoluminescence spectroscopy and layer-by-layer polish grinding methods, five distinct solidification zones were identified and investigated: primary, secondary, bottom interference, top interference, and final. These zones exhibit different stress profiles because of the disparities in solidification rates and glass transitions, which are affected by the thermal properties of the contacting materials and their heat transfer dynamics. A notable observation from the analysis of the stress distribution along z-axis is the near absence of stress at the bottom layer, which is accompanied by minor tensile stress at the glass-metal interface. In contrast, the middle layers display a non-uniform stress distribution within the xy-plane, with stress levels intensifying proximate to the glass-metal interfaces, indicating complex stress states within these regions. The uppermost layer exhibits a complex stress profile characterized by compressive and tensile strains that attain stable equilibrium without experiencing localized peaks near the glass-metal interfaces. This research comprehensively analyzes RS formation and entrapment in GTM seals, highlighting the importance of precise thermal management during cooling to achieve desired high-performance seals.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"13 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143443850","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":"Development of a Force Field for ATP – How Charge Scaling Controls Self Association","authors":"Tuan Minh Do, Nobuyuki Matubayasi, Dominik Horinek","doi":"10.1039/d4cp04270k","DOIUrl":"https://doi.org/10.1039/d4cp04270k","url":null,"abstract":"The discovery that ATP can prevent the aggregation of proteins and enhance their stability sparked significant interest in understanding the interactions between ATP and proteins. All-atom molecular dynamics simulations provide detailed insight into the underlying mechanism, while an appropriate force field must be developed. Existing force fields accurately describe the conformations of polyphosphates, but are not suitable for simulations at high ATP concentrations, because excessive self-aggregation occurs. We address this issue by scaling the atomic charges of the ATP anion and its counterions. The experimentally observed aggregation can be reproduced by using a scaling factor of 0.7 applied to the phosphate moiety of ATP and its counter ions. This charge scaling is in line with a physically motivated implicit account of polarization effects that sees increasing applications for simulations of ionic systems.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"42 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143443852","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":"Correction: Accelerated lithium-ion diffusion via a ligand ‘hopping’ mechanism in lithium enriched solvate ionic liquids","authors":"Timothy Harte, Bhagya Dharmasiri, Garima S. Dobhal, Tiffany R. Walsh, Luke C. Henderson","doi":"10.1039/d4cp90177k","DOIUrl":"https://doi.org/10.1039/d4cp90177k","url":null,"abstract":"Correction for ‘Accelerated lithium-ion diffusion <em>via</em> a ligand ‘hopping’ mechanism in lithium enriched solvate ionic liquids’ by Timothy Harte <em>et al.</em>, <em>Phys. Chem. Chem. Phys.</em>, 2023, <strong>25</strong>, 29614–29623, https://doi.org/10.1039/D3CP04666D.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"14 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143443849","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":"Estimating Advancing and Receding Contact Angles for Pure and Mixed Liquids on Smooth Solid Surfaces using PCP-SAFT Equation of State","authors":"Aliakbar Roosta, Sohrab Zendehboudi, Nima Rezaei","doi":"10.1039/d4cp04054f","DOIUrl":"https://doi.org/10.1039/d4cp04054f","url":null,"abstract":"Contact angle is an important measure of wetting in systems involving liquid-solid interfaces. This study focuses on estimating advancing and receding contact angles of pure and mixed liquids on smooth solid surfaces using perturbed-chain polar statistical associating fluid theory equation of state (PCP-SAFT EoS). For the receding contact angle, we propose a model in which the surface energy of solid containing a liquid film is approximated by the geometrical average of surface energies of the pure solid and liquid. The PCP-SAFT model is used to calculate the ratio of dispersion-to-total surface energy for diverse pure and mixed liquids. The results are validated against 104 experimental data points for advancing and receding contact angles, showing an average absolute relative deviation (AARD) of 7.4% for advancing angles and 10.6% for receding angles. In the contact angle models, there is an α-parameter in power term which is 0.75 and 0.5 for the advancing and receding contact angles, respectively. To assess the reliability of this α-parameter, we varied it and optimized it using experimental data. The optimized power term was found to be 0.74 for advancing and 0.48 for receding contact angle, and the AARD values slightly reduced to 7.2% and 10.5%, respectively. The optimized model parameter values are remarkably close to those based on the model assumptions (0.75 for advancing and 0.5 for receding), which validates the assumed values. The contact angle model combined with the PCP-SAFT framework allowed to accurately predict the advancing and receding contact angles of binary mixtures.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"81 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143462604","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":"Nano-wire Spin Hall Oscillator Fabricated by Novel Side-wall Transfer Lithography","authors":"Jialin Shi, Chenglong Zhang, Zhenhu Jin, Jiamin Chen","doi":"10.1039/d5cp00447k","DOIUrl":"https://doi.org/10.1039/d5cp00447k","url":null,"abstract":"Spin Hall nano oscillators (SHNOs) have garnered significant attention in the field of spintronics in recent years, particularly for their potential in neuromorphic computing. However, their sensitive regions, often below 200 nm, present considerable challenges for fabrication. The current mainstream approach relies on electron beam lithography (EBL) to define the shapes of SHNOs. While EBL is both costly and time-consuming, making it less ideal for the large-scale development and application of SHNOs. In this paper, we propose a novel fabrication method for nano-wire SHNOs using sidewall transfer lithography. This approach offers a practical solution to enhance fabrication efficiency while simultaneously reducing production costs, making it more suitable for mass production. Through experimental demonstrations, we validate the feasibility of this method and provide detailed insights into the sidewall transfer lithography process. Our findings suggest that this technique achieves higher theoretical accuracy than current fabrication methods, offering a cost-effective pathway for realizing large-scale arrays of SHNOs and promoting their application in advanced computing technologies.","PeriodicalId":99,"journal":{"name":"Physical Chemistry Chemical Physics","volume":"22 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143444004","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}