The Journal of Physical Chemistry A最新文献_第8页

Observations-Based Approach to the Estimation of the Oxidizing Capacity of the Atmosphere of Central London over the 2000–2024 Period 基于观测的2000-2024年伦敦市中心大气氧化能力估算方法

IF 3 2区化学

The Journal of Physical Chemistry A Pub Date : 2026-09-17 Epub Date: 2026-09-01 DOI: 10.1021/acs.jpca.6c02946

M. Anwar H. Khan, Richard G. Derwent, Frank A. F. Winiberg, Carl J. Percival, Dudley E. Shallcross

{"title":"Observations-Based Approach to the Estimation of the Oxidizing Capacity of the Atmosphere of Central London over the 2000–2024 Period","authors":"M. Anwar H. Khan, Richard G. Derwent, Frank A. F. Winiberg, Carl J. Percival, Dudley E. Shallcross","doi":"10.1021/acs.jpca.6c02946","DOIUrl":"https://doi.org/10.1021/acs.jpca.6c02946","url":null,"abstract":"An observations-based approach has been applied to theair qualitymonitoring data at the London Marylebone Road over the 2000–2024study period to estimate the oxidizing capacity of the atmospherein Central London. The mean of the daylight hours-averaged OH numberdensities is found to be 4.0 × 106 molecules cm–3, a value which is consistent with the OH concentrationsmeasured at different polluted sites in different campaigns. A strongseasonal cycle of OH number density is observed with a peak in summerand a trough in winter. Although there are large changes in emissionsfrom traffic and other sources and in ambient ozone levels in recentyears, the nonlinear regression fitted seasonal cycle through the24 years of daylight hours-averaged OH number densities exhibits aslight but highly statistically significant downward trend of (0.011± 0.0026) × 106 molecules cm–3, (0.3 ± 0.07) % per decade (where the quoted confidence intervalsrepresent 1 – σ and the 2 – σ confidencelimits do not encompass zero). The concept of OH collapses is introducedin the study and gives an idea about the impacts of air quality changeson the oxidizing capacity of the London atmosphere. The rise in thenumber of OH collapses during the early years of the study periodshown is driven by the increased direct emissions of NO2 from diesel-engined vehicles. The implication of a collapse shouldbe further researched; analysis could be undertaken on a shorter thanhourly time scale to assess the impact on OH collapse on a scale morecomparable to its lifetime. It should be noted that no long-term measurementsof HCHO or HONO were available, two key components of the OH budget,and these have been estimated as described in the text.","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"130 37","pages":"7450–7459"},"PeriodicalIF":3.0,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148985268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Chemical Space Perspective on Diastereomeric Barriers in Alkylperoxy-to-Hydroperoxyalkyl Isomerization 烷基过氧-氢过氧烷基异构化非对映体势垒的化学空间视角

IF 3 2区化学

The Journal of Physical Chemistry A Pub Date : 2026-09-17 Epub Date: 2026-09-04 DOI: 10.1021/acs.jpca.6c03201

Raghunathan Ramakrishnan

{"title":"A Chemical Space Perspective on Diastereomeric Barriers in Alkylperoxy-to-Hydroperoxyalkyl Isomerization","authors":"Raghunathan Ramakrishnan","doi":"10.1021/acs.jpca.6c03201","DOIUrl":"https://doi.org/10.1021/acs.jpca.6c03201","url":null,"abstract":"Low-temperaturehydrocarbon autoxidation involves radical intermediateswhose reactivity depends not only on the stereochemistry of the intermediatesthemselves, but also on that of the transient species encounteredalong the reaction path. This study offers large-scale evidence forthe importance of stereochemistry in low-temperature autoxidationby propagating stereochemical information from 498 C1–C7 hydrocarbons through radical formation, O2 addition,and the isomerization of alkylperoxy (ROO•) radicalsto hydroperoxyalkyl (•QOOH) radicals. The resultingdata set comprises density-functional-theory-level data for 5356 species,including 2324 cyclic diastereomeric transition states associatedwith 1162 unique ROO• → •QOOH isomerization reactions, with transition-state connectivityconfirmed by intrinsic reaction coordinate analysis. Explicit stereochemicaltreatment reveals that diastereomeric pathways may be either nearlydegenerate or separated by more than 60 kcal/mol, with the magnitudeof these differences governed by local steric strain, ring constraint,and the environments of the peroxyl-bearing and H-abstraction centers.These results show that constitutionally collapsed molecular representationscan systematically miss kinetically relevant reactive channels andprovide a foundation for stereochemistry-aware mechanism generation,rate estimation, and predictive combustion modeling.","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"130 37","pages":"7469–7480"},"PeriodicalIF":3.0,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148985168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

IR Spectroscopy of Gas-Phase Protonated Water–Acetonitrile Clusters: Comparison of the Clusters in the Condensed Phase and Gas Phase 气相质子化水-乙腈团簇的红外光谱分析：缩合相和气相团簇的比较

IF 3 2区化学

The Journal of Physical Chemistry A Pub Date : 2026-09-17 Epub Date: 2026-09-03 DOI: 10.1021/acs.jpca.6c03240

Kohei Chiba, Asuka Fujii

{"title":"IR Spectroscopy of Gas-Phase Protonated Water–Acetonitrile Clusters: Comparison of the Clusters in the Condensed Phase and Gas Phase","authors":"Kohei Chiba, Asuka Fujii","doi":"10.1021/acs.jpca.6c03240","DOIUrl":"https://doi.org/10.1021/acs.jpca.6c03240","url":null,"abstract":"We performed infrared photodissociation spectroscopyand theoreticalcomputations on gas-phase protonated water–acetonitrile clusters,H+[(H2O)m(CH3CN)n] (m = 1, n = 1–3; m = 2, n = 1–6; and m = 3, n = 5),to determine their cluster structures and compared their infraredspectra with previously reported spectra of protonated water clustersin acetonitrile solutions. For the (m = 2, n = 4) cluster, which serves as a model for the protonatedwater dimer in an acetonitrile solution, the band center of the hydrogen-bondedOH stretch absorption was observed at a lower frequency than thatin the solution spectra. This indicates that the formation of thesecond and subsequent solvation shells significantly weakens the hydrogenbonding between the protonated water dimer (ion core) and the firstsolvation shell in the solution phase. On the other hand, the spectrumof the (m = 3, n = 5) cluster, amodel of the protonated water trimer with a completed first solvationshell, showed a much better agreement with that of the solution phase,suggesting a tendency where an increase in the protonated clustersize reduces the influence of the second solvation shell.","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"130 37","pages":"7359–7365"},"PeriodicalIF":3.0,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148985267","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Unraveling the Catalytic Role of Metal- and Halide-Free Phosphonium Systems in CO2 Transformation 揭示无金属和无卤化物磷体系在CO2转化中的催化作用

IF 3 2区化学

The Journal of Physical Chemistry A Pub Date : 2026-09-17 Epub Date: 2026-09-01 DOI: 10.1021/acs.jpca.6c03483

Ahmed G. B. Hofny, Ashour A. Ahmed, Fatma S. M. Hassan, M. A. El Taher, Morad M. El-Hendawy

{"title":"Unraveling the Catalytic Role of Metal- and Halide-Free Phosphonium Systems in CO2 Transformation","authors":"Ahmed G. B. Hofny, Ashour A. Ahmed, Fatma S. M. Hassan, M. A. El Taher, Morad M. El-Hendawy","doi":"10.1021/acs.jpca.6c03483","DOIUrl":"https://doi.org/10.1021/acs.jpca.6c03483","url":null,"abstract":"The cycloaddition of CO2 to epoxides to formcycliccarbonates represents an attractive route toward sustainable chemicaltransformations. Herein, the catalytic performance of a halide- andmetal-free catalyst, tetramethylphosphonium acetate (TMPA), is investigatedusing density functional theory (DFT). Benchmark studies employing13 DFT functionals, including dispersion-corrected and nondispersion-correctedmethods, identified B3LYP-D3 as providing the closest agreement withexperimental reactivity. Using this framework, we systematically examinedthe effects of dispersion, solvation, and counterion substitutionon the rate-determining activation step. Implicit consideration ofexcess propylene oxide (PO) as the reaction medium dramatically lowersthe activation barrier by ∼16 kcal/mol, underscoring the criticalrole of solvent-assisted activation. In contrast, replacing the acetatecounterion with iodide transforms the reaction from a kineticallyaccessible and balanced catalytic cycle into a kinetically hinderedpathway, despite enhanced stabilization of the final cyclic carbonateproduct. These findings establish four key mechanistic principlesfor the rational design of efficient metal- and halide-free catalystsfor CO2 conversion: (i) excess reactants can play a criticalsolvent-like role and must be explicitly considered, (ii) the identityof the counterion in ionic catalysts strongly governs catalytic performance,(iii) directional noncovalent interactions are essential for efficienttransition-state organization, and (iv) optimal catalysts achievebalanced intermediate stabilization together with strong transition-statestabilization to maintain a kinetically accessible catalytic cycle.","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"130 37","pages":"7383–7393"},"PeriodicalIF":3.0,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148985297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Collision-Induced Formation and Dissociation of Benzene–Hexafluorobenzene–Benzene Trimers: A Chemical Dynamics Study 碰撞诱导苯-六氟苯-苯三聚体的形成和解离：化学动力学研究

IF 3 2区化学

The Journal of Physical Chemistry A Pub Date : 2026-09-17 Epub Date: 2026-09-04 DOI: 10.1021/acs.jpca.6c04646

Basudha Deb, Himashree Mahanta, Souvik Shaw, Amit Kumar Paul

{"title":"Collision-Induced Formation and Dissociation of Benzene–Hexafluorobenzene–Benzene Trimers: A Chemical Dynamics Study","authors":"Basudha Deb, Himashree Mahanta, Souvik Shaw, Amit Kumar Paul","doi":"10.1021/acs.jpca.6c04646","DOIUrl":"https://doi.org/10.1021/acs.jpca.6c04646","url":null,"abstract":"Inthis work, the collision-induced association of a benzene moleculewith a pre-existing benzene–hexafluorobenzene (Bz–HFB)dimer and the ensuing dissociation dynamics of the resulting trimercomplexes are investigated using computational chemical dynamics simulations.Trajectories were computed at 300, 500, 700, 1000, 1200, 1500, 1800,and 2000 K to examine the competition between trimer formation, dimerexchange, and dissociation. Stable trimer formation is found to beintrinsically rare and becomes increasingly unfavorable with increasingtemperature, occurring only at 300 K and between 500 and 1500 K, whileno stable trimers are observed at 1800 and 2000 K. Subsequently, thetrimers undergo either partial dissociation to yield dimer productsor complete fragmentation into three monomers. The formation of newdimers is considerably more probable than trimer formation. Amongthe product dimers, Bz(2)-HFB forms significantly more frequentlythan Bz(1)-Bz(2), reflecting the stronger Bz···HFBinteraction. The ensuing dissociation of the newly formed Bz-HFB dimersis faster than that of the benzene dimers, consistent with trendsreported for unimolecular dissociation. The dissociation of the originalBz-HFB complex closely resembles that of the isolated dimer. Theseresults provide a detailed molecular-level understanding of association-inducedcompeting reaction pathways in weakly bound aromatic clusters, providingnew insights into the dynamics of collision-driven cluster growthand fragmentation in the combustion environment.","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"130 37","pages":"7421–7431"},"PeriodicalIF":3.0,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148985338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of S···O Chalcogen-Bond Interaction: A Combined Protein Data Bank Survey and Theoretical Calculations S···O硫键相互作用的研究：一个组合蛋白质数据库的调查和理论计算

IF 3 2区化学

The Journal of Physical Chemistry A Pub Date : 2026-09-17 Epub Date: 2026-09-07 DOI: 10.1021/acs.jpca.6c03102

Heena Charaya, Anamika Ghosh, Riya Saha, Debabani Ganguly, Amrita Chakraborty, Shamik Chakraborty

{"title":"Investigation of S···O Chalcogen-Bond Interaction: A Combined Protein Data Bank Survey and Theoretical Calculations","authors":"Heena Charaya, Anamika Ghosh, Riya Saha, Debabani Ganguly, Amrita Chakraborty, Shamik Chakraborty","doi":"10.1021/acs.jpca.6c03102","DOIUrl":"https://doi.org/10.1021/acs.jpca.6c03102","url":null,"abstract":"Sulfur-containing heterocycles such as thiophene, thiazole,andthiadiazole frequently appear in biologically active molecules, althoughthe intrinsic nature of their S···O chalcogen-bonding(ChB) interactions in protein–ligand complexes is yet to becompletely understood. In this work, a comprehensive survey of theProtein Data Bank (December 2024 release) was carried out, identifyingmore than 3,000 crystal structures in which these heterocycles engagein chalcogen-bonding interaction. Among those, 1547 unique structuresshow S···O close contacts with the oxygen atom of theprotein carbonyl group and/or side chain. Statistical analysis ofdistance and angular distributions reveals distinct interaction preferencesacross the three heterocyclic families. Representative complexes wereexamined using truncated structures, enabling comparison between crystallographicgeometries and optimized gas-phase structures. Quantum chemical calculations,including AIM, NBO, ESP, and EDA analyses, show that electron-withdrawingsubstituents enhance the stability of S···O ChB interactionby increasing the positive potential on sulfur and lowering the energyof the<math><msubsup><mrow><mi>σ</mi></mrow><mrow><mrow><mi>C</mi></mrow><mrow><mo>−</mo></mrow><mrow><mi>S</mi></mrow></mrow><mrow><mo>*</mo></mrow></msubsup></math>orbital (LUMO). Thiadiazoles exhibit thestrongest intrinsic ChB ability, followed by thiazoles and thiophenes.Together, these results provide a detailed molecular-level understandingof S···O ChB interaction and insights into the structuraland energetic factors governing the interaction of sulfur-containingligands within protein environments.","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"130 37","pages":"7345–7358"},"PeriodicalIF":3.0,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148985174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Retraction of “Broadband Microwave Spectroscopy of 2-Furanyloxy Radical: Primary Pyrolysis Product of the Second-Generation Biofuel 2-Methoxyfuran” “2-呋喃氧基自由基的宽带微波光谱：第二代生物燃料2-甲氧基呋喃的主要热解产物”的撤回

IF 3 2区化学

The Journal of Physical Chemistry A Pub Date : 2026-09-17 Epub Date: 2026-09-04 DOI: 10.1021/acs.jpca.6c05600

Chamara Abeysekera, A.O. Hernandez-Castillo, John F. Stanton, Timothy S. Zwier

引用次数: 0

Quantified Interfacial Affinity of Hydrogen Sulfate and Sulfate Speciation in Model Marine Aerosol Particles 模拟海洋气溶胶颗粒中硫酸氢的界面亲和和硫酸盐形态的量化

IF 3 2区化学

The Journal of Physical Chemistry A Pub Date : 2026-09-17 Epub Date: 2026-09-04 DOI: 10.1021/acs.jpca.6c04034

Leslie M. Ritchie, Madison B. Lester, Arun K. Sharma, Joshua D. Patterson

{"title":"Quantified Interfacial Affinity of Hydrogen Sulfate and Sulfate Speciation in Model Marine Aerosol Particles","authors":"Leslie M. Ritchie, Madison B. Lester, Arun K. Sharma, Joshua D. Patterson","doi":"10.1021/acs.jpca.6c04034","DOIUrl":"https://doi.org/10.1021/acs.jpca.6c04034","url":null,"abstract":"Heterogeneous reactionsoccurring in atmospheric aerosols are crucialcomponents of multiple chemical reaction cycles. Sulfate species exertsubstantial influence on many heterogeneous reaction mechanisms dueto their abundance and speciation. Despite the importance of sulfatespecies on heterogeneous reactions, quantitative descriptions of interfacialaffinity and sulfate species partitioning at interfaces remain incomplete.Here, we quantify the interfacial properties of HSO4–, using cetyltrimethylammonium hydrogen sulfate (CTAHS)reverse micelles (RMs), as model marine aerosol particles. Infraredspectra (IR) of CTAHS RMs were collected and analyzed using multivariatecurve resolution-alternating least-squares (MCR-ALS). MCR-ALS analysisreveals that four distinct species contribute to the observed IR spectra,which we assign as CTA+-HSO4– contact pairs (CPs), interfacial HSO4–, core HSO4–, and core SO42–. Computational studies reveal that the CTA+-HSO4– CPs exist in two distinctorientations at the interface. Spectral contributions from each chemicalspecies are used to determine the quantitative interfacial affinity(χInt.) of HSO4–. Ourobservations indicate that the cationic charge of the interface altersthe ionic distribution of sulfate species compared to air–waterinterfaces, placing H3O+ below HSO4–.","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"130 37","pages":"7460–7468"},"PeriodicalIF":3.0,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148985298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Conformational Analysis, Intramolecular Interactions, and Anharmonic Vibrational Spectra of the 2-Chloroethyl Chalcogenol Triad (X = O, S, Se) 2-氯乙基苯酚三元化合物（X = O， S, Se）的构象分析、分子内相互作用和非调和振动谱

IF 3 2区化学

The Journal of Physical Chemistry A Pub Date : 2026-09-17 Epub Date: 2026-09-09 DOI: 10.1021/acs.jpca.6c03047

Martina Kieninger, Aline Katz, Oscar N. Ventura

{"title":"Conformational Analysis, Intramolecular Interactions, and Anharmonic Vibrational Spectra of the 2-Chloroethyl Chalcogenol Triad (X = O, S, Se)","authors":"Martina Kieninger, Aline Katz, Oscar N. Ventura","doi":"10.1021/acs.jpca.6c03047","DOIUrl":"https://doi.org/10.1021/acs.jpca.6c03047","url":null,"abstract":"We present a systematic computationalstudy of the conformationalspace, intramolecular bonding, and anharmonic vibrational spectraof 2-chloroethanol (ClCH2CH2OH), 2-chloroethanethiol(ClCH2CH2SH), and 2-chloroethaneselenol (ClCH2CH2SeH), together with their 1-chloro isomers.Conformational searches with the CREST/iMTD-GC algorithm followedby DFT optimization identify low-energy gauche conformers stabilizedby intramolecular X–H•••Cl interactions;this gauche X–H•••Cl structure is theglobal minimum for the alcohol, whereas for the thiol and selenol,the global minimum is an anti-conformer and the gauche X–H•••Clform lies only 0.1 and 0.8 kcal/mol higher. Composite coupled-clusterenergetics (SVECV-f12 for O/S; DLPNO–CCSD(T)/CBS for Se) confirmthe DFT conformational ordering, with mean absolute deviations of0.10–0.14 kcal/mol and only small deviations for quasi-degenerateconformers. Natural population analysis reveals a progressive polarityreversal of the chalcogen from O to Se, while second-order NBO analysisshows that the gauche preference is hyperconjugative in origin, withnegligible direct Cl lone-pair donation into σ*(X–H).Uniform double-hybrid (B2PLYP-D3) GVPT2 calculations yield well-behaved,monotonically decreasing anharmonic X–H shifts (−188,−104, and −90 cm–1 for O–H,S–H, and Se–H) in both isomeric series and uniformlynegative zero-point energy corrections. We also document a pronouncedsensitivity of numerically differentiated quartic force fields toreference-geometry convergence and functional choice for the heavierchalcogens, with practical recommendations for anharmonic studiesof Se-containing molecules.","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"130 37","pages":"7324–7335"},"PeriodicalIF":3.0,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148985199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Existence of Distinct Equilibrium Configurations under Orienting External Electric Fields 定向外电场下不同平衡构型的存在性

IF 3 2区化学

The Journal of Physical Chemistry A Pub Date : 2026-09-17 Epub Date: 2026-09-02 DOI: 10.1021/acs.jpca.6c03020

Duc Anh Lai, Devin A. Matthews

{"title":"Existence of Distinct Equilibrium Configurations under Orienting External Electric Fields","authors":"Duc Anh Lai, Devin A. Matthews","doi":"10.1021/acs.jpca.6c03020","DOIUrl":"https://doi.org/10.1021/acs.jpca.6c03020","url":null,"abstract":"Oriented external electric fields (OEEFs) are ubiquitousin chemistry;however, the effects of fields applied in different directions onmolecular systems remain underexplored. A major challenge is thatan applied field exerts a torque on a molecule, reorienting the molecularframe and complicating the interpretation of orientation-dependentelectric-field effects. Thus, free polar molecules experience orientingrather than oriented fields, such that the field response drives themolecular orientation rather than the other way around. In this work,we explore a new regime of distinct molecular equilibrium configurationsin the presence of OEEFs, differing in the relative direction of theexternal field and the molecular frame. While static dipole momentstypically dominate molecular responses to external electric fields,these equilibria are enabled by exploiting molecular polarizability.These distinct “directomers” exhibit unique electronicand nuclear configurations, particularly in their low-lying excitedstates. We employ oriented electric field vectors referenced to amolecule-fixed principal axis frame along with hybrid analytical-numericalgeometry optimization in order to explore the rotational potentialenergy surface (rPES), as well as a simply analytic model based onequilibrium electrical properties which captures the double-well characterof the rPES, including some geometry relaxation effects.","PeriodicalId":59,"journal":{"name":"The Journal of Physical Chemistry A","volume":"130 37","pages":"7312–7323"},"PeriodicalIF":3.0,"publicationDate":"2026-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148985210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0