1
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Roman MJ, Knight AG, Moon DR, Lane PD, Costen ML, McKendrick KG. Distinguishing Mechanisms for Reactive Uptake at Liquid Surfaces via Angular Distributions of Inelastically Scattered Molecules. J Phys Chem A 2024; 128:5166-5174. [PMID: 38915192 PMCID: PMC11229065 DOI: 10.1021/acs.jpca.4c02917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Angular distributions of OH inelastically scattered from the surfaces of the reactive hydrocarbon liquids squalane (fully saturated) and squalene (partially unsaturated) have been measured. A pulsed, rotationally cold molecular beam (Ei = 35 kJ mol-1) of OH was scattered from refreshed liquid surfaces in a vacuum. Spatially and temporally resolved OH number densities were measured by pulsed, planar laser-induced fluorescence. Results are compared with those for the inert liquid perfluoropolyether. The clearly asymmetric distributions for 45° incidence add to the weight of evidence for predominantly impulsive scattering from all three liquids. However, we propose that significant differences in their shapes may be diagnostic of contrasting reaction mechanisms. Direct, near-specular trajectories survive preferentially on squalene, consistent with an addition mechanism removing those at more backward angles. This trend is reversed for squalane, as expected for direct abstraction. The results reinforce the need to consider the effects of composition-dependent contributions from different reaction mechanisms in the modeling of OH-aging of atmospheric aerosol particles.
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Affiliation(s)
- Maksymilian J Roman
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Adam G Knight
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Daniel R Moon
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Paul D Lane
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Matthew L Costen
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
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2
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Li J, Guo H, Li J. Energy- and Angle-Resolved Scattering of Ne from Dodecane Liquid Surfaces: Theory Corroborating Experiment. J Phys Chem Lett 2024; 15:5824-5830. [PMID: 38787404 DOI: 10.1021/acs.jpclett.4c00994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Motivated by recent experimental work by the Neumark group, we present here an all-atom molecular dynamics study of Ne scattering from a dodecane liquid surface with the objective of elucidating the fundamental aspects of gas-liquid dynamics. Using a fine-tuned force field, the GPU-accelerated simulations reproduced semiquantitatively the energy- and angle-resolved experimental results. The branching ratio between the impulsive scattering (IS) and thermal desorption (TD) channels exhibits a clear correlation with the incidence energy (Ei) and angle. Ne atoms with lower Ei values are more likely to be trapped, yielding an increased TD ratio. For a given Ei, a large incidence angle led to a higher IS ratio. The energy transfer between Ne atoms and liquid dodecane was found to be more sensitive to the deflection angle than to the incidence or reflection angle. With an increasing deflection angle, the fractional energy loss increases, suggesting that more kinetic energy is transferred to the liquid.
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Affiliation(s)
- Junhong Li
- School of Chemistry and Chemical Engineering and Chongqing Key Laboratory of Chemical Theory and Mechanism, Chongqing University, Chongqing 401331, China
| | - Hua Guo
- Department of Chemistry and Chemical Biology, Center for Computational Chemistry, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Jun Li
- School of Chemistry and Chemical Engineering and Chongqing Key Laboratory of Chemical Theory and Mechanism, Chongqing University, Chongqing 401331, China
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3
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Gleichweit MJ, Azizbaig Mohajer M, Borgeaud Dit Avocat DP, Divéky ME, David G, Signorell R. Unexpected concentration dependence of the mass accommodation coefficient of water on aqueous triethylene glycol droplets. Phys Chem Chem Phys 2024; 26:16296-16308. [PMID: 38804833 PMCID: PMC11154172 DOI: 10.1039/d4cp00966e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Accepted: 05/15/2024] [Indexed: 05/29/2024]
Abstract
The mass accommodation coefficient αM of water on aqueous triethylene glycol droplets was determined for water mole fractions in the range xmol = 0.1-0.93 and temperatures between 21 and 26 °C from modulated Mie scattering measurement on single optically-trapped droplets in combination with a kinetic multilayer model. αM reaches minimum values around 0.005 at a critical water concentration of xmol = 0.38, and increases with decreasing water content to a value of ≈0.1 for almost pure triethylene glycol droplets, essentially independent of the temperature. Above xmol = 0.38, αM first increases with increasing water content and then stabilises at a value of ≈0.1 at the lowest temperatures, while at the highest temperature its value remains around 0.005. We analysed the unexpected concentration and temperature dependence with a previously proposed two-step model for mass accommodation which provides concentration and temperature-dependent activation enthalpies and entropies. We suggest that the unexpected minimum in αM at intermediate water concentrations might arise from a more or less saturated hydrogen-bond network that forms at the droplet surface.
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Affiliation(s)
- Michael J Gleichweit
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.
| | | | | | - Matúš E Divéky
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.
| | - Grégory David
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.
| | - Ruth Signorell
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.
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4
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Schatz GC, Wodtke AM, Yang X. Spiers Memorial Lecture: New directions in molecular scattering. Faraday Discuss 2024. [PMID: 38764350 DOI: 10.1039/d4fd00015c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/21/2024]
Abstract
The field of molecular scattering is reviewed as it pertains to gas-gas as well as gas-surface chemical reaction dynamics. We emphasize the importance of collaboration of experiment and theory, from which new directions of research are being pursued on increasingly complex problems. We review both experimental and theoretical advances that provide the modern toolbox available to molecular-scattering studies. We distinguish between two classes of work. The first involves simple systems and uses experiment to validate theory so that from the validated theory, one may learn far more than could ever be measured in the laboratory. The second class involves problems of great complexity that would be difficult or impossible to understand without a partnership of experiment and theory. Key topics covered in this review include crossed-beams reactive scattering and scattering at extremely low energies, where quantum effects dominate. They also include scattering from surfaces, reactive scattering and kinetics at surfaces, and scattering work done at liquid surfaces. The review closes with thoughts on future promising directions of research.
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Affiliation(s)
- George C Schatz
- Dept of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
| | - Alec M Wodtke
- Institute for Physical Chemistry, Georg August University, Goettingen, Germany
- Max Planck Institute for Multidisciplinary Natural Sciences, Goettingen, Germany.
- International Center for the Advanced Studies of Energy Conversion, Georg August University, Goettingen, Germany
| | - Xueming Yang
- Dalian Institute for Chemical Physics, Chinese Academy of Sciences, Dalian, China
- Department of Chemistry, College of Science, Southern University of Science and Technology, Shenzhen, China
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5
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Saric S, Yang W, Neumark DM. Molecular beam scattering of ammonia from a dodecane flat liquid jet. Faraday Discuss 2024. [PMID: 38757959 DOI: 10.1039/d3fd00169e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2024]
Abstract
The evaporation and scattering of ND3 from a dodecane flat liquid jet are investigated and the results are compared with previous studies on molecular beam scattering from liquid surfaces. Evaporation is well-described by a Maxwell-Boltzmann flux distribution with a cos θ angular distribution at the liquid temperature. Scattering experiments at Ei = 28.8 kJ mol-1 over a range of deflection angles show evidence for impulsive scattering and thermal desorption. At a deflection angle of 90°, the thermal desorption fraction is 0.49, which is higher than that of other molecules previously scattered from dodecane and consistent with work performed on NH3 scattering from a squalane-wetted wheel. ND3 scattering from dodecane results in super-specular scattering, as seen in previous experiments on dodecane. The impulsive scattering channel is fitted to a "soft-sphere" model, yielding an effective surface mass of 55 amu and an internal excitation of 5.08 kJ mol-1. Overall, impulsively scattered ND3 behaves similarly to other small molecules scattered from dodecane.
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Affiliation(s)
- Steven Saric
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Walt Yang
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Daniel M Neumark
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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6
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Gao XF, Nathanson GM. Exploring Gas-Liquid Reactions with Microjets: Lessons We Are Learning. Acc Chem Res 2022; 55:3294-3302. [PMID: 36378763 DOI: 10.1021/acs.accounts.2c00602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Liquid water is all around us: at the beach, in a cloud, from a faucet, inside a spray tower, covering our lungs. It is fascinating to imagine what happens to a reactive gas molecule as it approaches the surface of water in these examples. Some incoming molecules may first be deflected away after colliding with an evaporating water molecule. Those that do strike surface H2O or other surface species may bounce directly off or become momentarily trapped through hydrogen bonding or other attractive forces. The adsorbed gas molecule can then desorb immediately or instead dissolve, passing through the interfacial region and into the bulk, perhaps diffusing back to the surface and evaporating before reacting. Alternatively, it may react with solute or water molecules in the interfacial or bulk regions, and a reaction intermediate or the final product may then desorb into the gas phase. Building a "blow by blow" picture of these pathways is challenging for vacuum-based techniques because of the high vapor pressure of water. In particular, collisions within the thick vapor cloud created by evaporating molecules just above the surface scramble the trajectories and internal states of the gaseous target molecules, hindering construction of gas-liquid reaction mechanisms at the atomic scale that we strive to map out.The introduction of the microjet in 1988 by Faubel, Schlemmer, and Toennies opened up entirely new possibilities. Their inspired solution seems so simple: narrow the end of a glass tube to a diameter smaller than the mean free path of the vapor molecules and then push the liquid through the tube at speeds of a car on a highway. The narrow liquid stream creates a sparse vapor cloud, with water molecules spaced far enough apart that they and the reactant gases interact, at most, weakly. Experimentalists, however, confront a host of challenges: nozzle clogging, unstable jetting, searching for vacuum-compatible solutions, measuring low signal levels, and teasing out artifacts because the slender jet is the smallest surface in the vacuum chamber. In this Account, we describe lessons that we are learning as we explore gases (DCl, (HCOOH)2, N2O5) reacting with water molecules and solute ions in the near-interfacial region of these fast-flowing aqueous microjets.
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Affiliation(s)
- Xiao-Fei Gao
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Gilbert M Nathanson
- Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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7
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Chien TE, Hohmann L, Harding DJ. Near-ambient pressure velocity map imaging. J Chem Phys 2022; 157:034201. [DOI: 10.1063/5.0098495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We present a new velocity map imaging instrument for studying molecular beam surface scattering in a near-ambient pressure (NAP-VMI) environment. The instrument offers the possibility to study chemical reaction dynamics and kinetics where higher pressures are either desired or unavoidable, adding a new tool to help close the “pressure gap” between surface science and applied catalysis. NAP-VMI conditions are created by two sets of ion optics that guide ions through an aperture and map their velocities. The aperture separates the high pressure ionization region and maintains the necessary vacuum in the detector region. The performance of the NAP-VMI is demonstrated with results from N2O photodissociation and N2 scattering from a Pd(110) surface, which are compared under vacuum and at near-ambient pressure (1 × 10−3 mbar). NAP-VMI has the potential to be applied to, and useful for, a broader range of experiments, including photoelectron spectroscopy and scattering with liquid microjets.
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Affiliation(s)
- Tzu-En Chien
- Department of Chemical Engineering, KTH Royal Institute of Technology, Stockholm 100 44, Sweden
| | - Lea Hohmann
- Department of Chemical Engineering, KTH Royal Institute of Technology, Stockholm 100 44, Sweden
| | - Dan J. Harding
- Department of Chemical Engineering, KTH Royal Institute of Technology, Stockholm 100 44, Sweden
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8
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Manson JR, Miret-Artés S. Atom-surface scattering in the classical multiphonon regime. Phys Chem Chem Phys 2022; 24:16942-16972. [PMID: 35796229 DOI: 10.1039/d2cp01144a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Many experiments that utilize beams of incident atoms colliding with surfaces as a probe of surface properties are carried out at large energies, high temperatures and with large mass atoms. Under these conditions the scattering process does not exhibit quantum mechanical properties such as diffraction or single-phonon excitation, but rather can be treated with classical physics. This is a review of work carried out by the authors over a span of several years to develop theoretical frameworks using classical physics for describing the scattering interactions of atom with surfaces.
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Affiliation(s)
- J R Manson
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal, 4, 20018 Donostia-San Sebastian, Spain.,Department of Physics and Astronomy, Clemson University, Clemson, South Carolina 29634, USA
| | - S Miret-Artés
- Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal, 4, 20018 Donostia-San Sebastian, Spain.,Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 123, 28006 Madrid, Spain.
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9
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Lee C, Pohl MN, Ramphal IA, Yang W, Winter B, Abel B, Neumark DM. Evaporation and Molecular Beam Scattering from a Flat Liquid Jet. J Phys Chem A 2022; 126:3373-3383. [PMID: 35579333 DOI: 10.1021/acs.jpca.2c01174] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An experimental setup for molecular beam scattering from flat liquid sheets has been developed, with the goal of studying reactions at gas-liquid interfaces for volatile liquids. Specifically, a crossed molecular beam instrument that can measure angular and translational energy distributions of scattered products has been adapted for liquid jet scattering. A microfluidic chip is used to create a stable flat liquid sheet inside vacuum from which scattering occurs, and both evaporation and scattering from this sheet are characterized using a rotatable mass spectrometer that can measure product time-of-flight distributions. This article describes the instrument and reports on the first measurements of evaporation of dodecane and Ne from a Ne-doped dodecane flat jet, as well as scattering of Ne from a flat jet of pure dodecane.
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Affiliation(s)
- Chin Lee
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Marvin N Pohl
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Isaac A Ramphal
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Walt Yang
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Bernd Winter
- Molecular Physics, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Bernd Abel
- Department of Functional Surfaces, Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318 Leipzig, Germany.,Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University of Leipzig, Linnéstrasse 3, 04318 Leipzig, Germany
| | - Daniel M Neumark
- Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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10
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Baines KH, Nikolić D, Cutts JA, Delitsky ML, Renard JB, Madzunkov SM, Barge LM, Mousis O, Wilson C, Limaye SS, Verdier N. Investigation of Venus Cloud Aerosol and Gas Composition Including Potential Biogenic Materials via an Aerosol-Sampling Instrument Package. ASTROBIOLOGY 2021; 21:1316-1323. [PMID: 33944604 DOI: 10.1089/ast.2021.0001] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A lightweight, low-power instrument package to measure, in situ, both (1) the local gaseous environment and (2) the composition and microphysical properties of attendant venusian aerosols is presented. This Aerosol-Sampling Instrument Package (ASIP) would be used to explore cloud chemical and possibly biotic processes on future aerial missions such as multiweek balloon missions and on short-duration (<1 h) probes on Venus and potentially on other cloudy worlds such as Titan, the Ice Giants, and Saturn. A quadrupole ion-trap mass spectrometer (QITMS; Madzunkov and Nikolić, J Am Soc Mass Spectrom 25:1841-1852, 2014) fed alternately by (1) an aerosol separator that injects only aerosols into a vaporizer and mass spectrometer and (2) the pure aerosol-filtered atmosphere, achieves the compositional measurements. Aerosols vaporized <600°C are measured over atomic mass ranges from 2 to 300 AMU at <0.02 AMU resolution, sufficient to measure trace materials, their isotopic ratios, and potential biogenic materials embedded within H2SO4 aerosols, to better than 20% in <300 s for H2SO4 -relative abundances of 2 × 10-9. An integrated lightweight, compact nephelometer/particle-counter determines the number density and particle sizes of the sampled aerosols.
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Affiliation(s)
- Kevin H Baines
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Dragan Nikolić
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - James A Cutts
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | | | | | - Stojan M Madzunkov
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Laura M Barge
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
| | - Olivier Mousis
- Aix Marseille Université, CNRS, CNES, LAM, Marseille, France
| | | | - Sanjay S Limaye
- Space Science and Engineering Center, University of Wisconsin-Madison, Wisconsin, USA
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11
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Zeng M, Wilson KR. Experimental evidence that halogen bonding catalyzes the heterogeneous chlorination of alkenes in submicron liquid droplets. Chem Sci 2021; 12:10455-10466. [PMID: 34447538 PMCID: PMC8356749 DOI: 10.1039/d1sc02662c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 07/09/2021] [Indexed: 12/21/2022] Open
Abstract
A key challenge in predicting the multiphase chemistry of aerosols and droplets is connecting reaction probabilities, observed in an experiment, with the kinetics of individual elementary steps that control the chemistry that occurs across a gas/liquid interface. Here we report evidence that oxygenated molecules accelerate the heterogeneous reaction rate of chlorine gas with an alkene (squalene, Sqe) in submicron droplets. The effective reaction probability for Sqe is sensitive to both the aerosol composition and gas phase environment. In binary aerosol mixtures with 2-decyl-1-tetradecanol, linoleic acid and oleic acid, Sqe reacts 12-23× more rapidly than in a pure aerosol. In contrast, the reactivity of Sqe is diminished by 3× when mixed with an alkane. Additionally, small oxygenated molecules in the gas phase (water, ethanol, acetone, and acetic acid) accelerate (up to 10×) the heterogeneous chlorination rate of Sqe. The overall reaction mechanism is not altered by the presence of these aerosol and gas phase additives, suggesting instead that they act as catalysts. Since the largest rate acceleration occurs in the presence of oxygenated molecules, we conclude that halogen bonding enhances reactivity by slowing the desorption kinetics of Cl2 at the interface, in a way that is analogous to decreasing temperature. These results highlight the importance of relatively weak interactions in controlling the speed of multiphase reactions important for atmospheric and indoor environments.
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Affiliation(s)
- Meirong Zeng
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
| | - Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
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12
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Diveky ME, Gleichweit MJ, Roy S, Signorell R. Shining New Light on the Kinetics of Water Uptake by Organic Aerosol Particles. J Phys Chem A 2021; 125:3528-3548. [PMID: 33739837 DOI: 10.1021/acs.jpca.1c00202] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The uptake of water vapor by various organic aerosols is important in a number of applications ranging from medical delivery of pharmaceutical aerosols to cloud formation in the atmosphere. The coefficient that describes the probability that the impinging gas-phase molecule sticks to the surface of interest is called the mass accommodation coefficient, αM. Despite the importance of this coefficient for the description of water uptake kinetics, accurate values are still lacking for many systems. In this Feature Article, we present various experimental techniques that have been evoked in the literature to study the interfacial transport of water and discuss the corresponding strengths and limitations. This includes our recently developed technique called photothermal single-particle spectroscopy (PSPS). The PSPS technique allows for a retrieval of αM values from three independent, yet simultaneous measurements operating close to equilibrium, providing a robust assessment of interfacial mass transport. We review the currently available data for αM for water on various organics and discuss the few studies that address the temperature and relative humidity dependence of αM for water on organics. The knowledge of the latter, for example, is crucial to assess the water uptake kinetics of organic aerosols in the Earth's atmosphere. Finally, we argue that PSPS might also be a viable method to better restrict the αM value for water on liquid water.
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Affiliation(s)
- Matus E Diveky
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Michael J Gleichweit
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Sandra Roy
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
| | - Ruth Signorell
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 2, CH-8093 Zürich, Switzerland
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13
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Winter L, Bhuin RG, Lexow M, Maier F, Steinrück HP. On the adsorption of n-butane on alkyl imidazolium ionic liquids with different anions using a new molecular beam setup. J Chem Phys 2020; 153:214706. [DOI: 10.1063/5.0028156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Leonhard Winter
- Lehrstuhl für Physikalische Chemie 2, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
| | - Radha G. Bhuin
- Lehrstuhl für Physikalische Chemie 2, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
| | - Matthias Lexow
- Lehrstuhl für Physikalische Chemie 2, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
| | - Florian Maier
- Lehrstuhl für Physikalische Chemie 2, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
| | - Hans-Peter Steinrück
- Lehrstuhl für Physikalische Chemie 2, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany
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14
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Xu C, Treadway CM, Murray VJ, Minton TK, Malaska MJ, Cable ML, Hofmann AE. Inelastic scattering dynamics of naphthalene and 2-octanone on highly oriented pyrolytic graphite. J Chem Phys 2020; 152:244709. [PMID: 32610992 DOI: 10.1063/5.0011958] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The inelastic scattering dynamics of the isobaric molecules, naphthalene (C10H8) and 2-octanone (C8H16O), on highly oriented pyrolytic graphite (HOPG) have been investigated as part of a broader effort to inform the inlet design of a mass spectrometer for the analysis of atmospheric gases during a flyby mission through the atmosphere of a planet or moon. Molecular beam-surface scattering experiments were conducted, and the scattered products were detected with the use of a rotatable mass spectrometer detector. Continuous, supersonic beams were prepared, with average incident translational energies, ⟨Ei⟩, of 247.3 kJ mol-1 and 538.2 kJ mol-1 for naphthalene and 268.6 kJ mol-1 and 433.8 kJ mol-1 for 2-octanone. These beams were directed toward an HOPG surface, held at 530 K, at incident angles, θi, of 30°, 45°, and 70°, and scattered products were detected as functions of their translational energies and scattering angles. The scattering dynamics of both molecules are very similar and mimic the scattering of atoms and small molecules on rough surfaces, where parallel momentum is not conserved, suggesting that the dynamics are dominated by a corrugated interaction potential between the incident molecule and the surface. The effective corrugation of the molecule-surface interaction is apparently caused by the structure of the incident molecule and the consequent myriad available energy transfer pathways between the molecule and the surface during a complex collision event. In addition, the HOPG surface contributes to the corrugation of the interaction potential because it can absorb significant energy from collisions with incident molecules that have high mass and incident energy. Small differences in the scattering dynamics of the two molecules are inferred to arise from the details of the molecule-surface interaction potential, with 2-octanone exhibiting dynamics that suggest a slightly stronger interaction with the surface than naphthalene. These results add to a growing body of work on the scattering dynamics of organic molecules on HOPG, from which insight into the hypervelocity sampling and analysis of such molecules may be obtained.
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Affiliation(s)
- Chenbiao Xu
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, USA
| | - Cal M Treadway
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, USA
| | - Vanessa J Murray
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, USA
| | - Timothy K Minton
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, USA
| | - Michael J Malaska
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, California 91109, USA
| | - Morgan L Cable
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, California 91109, USA
| | - Amy E Hofmann
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, California 91109, USA
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15
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McNally MJ, Galinis G, Youle O, Petr M, Prucek R, Machala L, von Haeften K. Silver nanoparticles by atomic vapour deposition on an alcohol micro-jet. NANOSCALE ADVANCES 2019; 1:4041-4051. [PMID: 36132097 PMCID: PMC9418456 DOI: 10.1039/c9na00347a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 09/05/2019] [Indexed: 05/13/2023]
Abstract
We achieved sputter deposition of silver atoms onto liquid alcohols by injection of solvents into vacuum via a liquid microjet. Mixing silver atoms into ethanol by this method produced metallic silver nanoparticles. These had a broad, log-normal size distribution, with median size between 3.3 ± 1.4 nm and 2.0 ± 0.7 nm, depending on experiment geometry; and a broad plasmon absorption band centred around 450 nm. We also deposited silver atoms into a solution of colloidal silica nanoparticles, generating silver-decorated silica particles with consistent decoration of almost one silver particle to each silica sphere. The silver-silica mixture showed increased colloidal stability and yield of silver, along with a narrowed size distribution and a narrower plasmon band blue-shifted to 410 nm. Significant methanol loss of 1.65 × 10-7 mol MeOH per g per s from the mature silver-silica solutions suggests we have reproduced known silica supported silver catalysts. The excellent distribution of silver on each silica sphere shows this technique has potential to improve the distribution of catalytically active particles in supported catalysts.
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Affiliation(s)
- Michael J McNally
- Department of Physics and Astronomy, University of Leicester Leicester UK
| | - Gediminas Galinis
- Department of Physics and Astronomy, University of Leicester Leicester UK
| | - Oliver Youle
- Department of Physics and Astronomy, University of Leicester Leicester UK
- Department of Engineering, University of Leicester Leicester UK
| | - Martin Petr
- Regional Centre of Advanced Technologies and Materials (RCPTM), Faculty of Science, Palacký University Olomouc Olomouc Czech Republic
| | - Robert Prucek
- Regional Centre of Advanced Technologies and Materials (RCPTM), Faculty of Science, Palacký University Olomouc Olomouc Czech Republic
| | - Libor Machala
- Regional Centre of Advanced Technologies and Materials (RCPTM), Faculty of Science, Palacký University Olomouc Olomouc Czech Republic
| | - Klaus von Haeften
- Department of Physics and Astronomy, University of Leicester Leicester UK
- Kanano GmbH 89077 Ulm Germany
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16
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Bianchini RH, Roman MJ, Costen ML, McKendrick KG. Real-space laser-induced fluorescence imaging applied to gas-liquid interfacial scattering. J Chem Phys 2019. [DOI: 10.1063/1.5110517] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Robert H. Bianchini
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Maksymilian J. Roman
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Matthew L. Costen
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Kenneth G. McKendrick
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
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17
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Wiegel AA, Liu MJ, Hinsberg WD, Wilson KR, Houle FA. Diffusive confinement of free radical intermediates in the OH radical oxidation of semisolid aerosols. Phys Chem Chem Phys 2018; 19:6814-6830. [PMID: 28218326 DOI: 10.1039/c7cp00696a] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Multiphase chemical reactions (gas + solid/liquid) involve a complex interplay between bulk and interface chemistry, diffusion, evaporation, and condensation. Reactions of atmospheric aerosols are an important example of this type of chemistry: the rich array of particle phase states and multiphase transformation pathways produce diverse but poorly understood interactions between chemistry and transport. Their chemistry is of intrinsic interest because of their role in controlling climate. Their characteristics also make them useful models for the study of principles of reactivity of condensed materials under confined conditions. In previous work, we have reported a computational study of the oxidation chemistry of a liquid aliphatic aerosol. In this study, we extend the calculations to investigate nearly the same reactions at a semisolid gas-aerosol interface. A reaction-diffusion model for heterogeneous oxidation of triacontane by hydroxyl radicals (OH) is described, and its predictions are compared to measurements of aerosol size and composition, which evolve continuously during oxidation. These results are also explicitly compared to those obtained for the corresponding liquid system, squalane, to pinpoint salient elements controlling reactivity. The diffusive confinement of the free radical intermediates at the interface results in enhanced importance of a few specific chemical processes such as the involvement of aldehydes in fragmentation and evaporation, and a significant role of radical-radical reactions in product formation. The simulations show that under typical laboratory conditions semisolid aerosols have highly oxidized nanometer-scale interfaces that encapsulate an unreacted core and may confer distinct optical properties and enhanced hygroscopicity. This highly oxidized layer dynamically evolves with reaction, which we propose to result in plasticization. The validated model is used to predict chemistry under atmospheric conditions, where the OH radical concentration is much lower. The oxidation reactions are more strongly influenced by diffusion in the particle, resulting in a more liquid-like character.
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Affiliation(s)
- Aaron A Wiegel
- Lawrence Berkeley National Laboratory, Chemical Sciences Division, Berkeley, CA 94702, USA.
| | - Matthew J Liu
- Lawrence Berkeley National Laboratory, Chemical Sciences Division, Berkeley, CA 94702, USA. and University of California, Berkeley, Department of Chemical and Biomolecular Engineering, Berkeley, CA 94702, USA
| | | | - Kevin R Wilson
- Lawrence Berkeley National Laboratory, Chemical Sciences Division, Berkeley, CA 94702, USA.
| | - Frances A Houle
- Lawrence Berkeley National Laboratory, Chemical Sciences Division, Berkeley, CA 94702, USA.
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18
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Bzdek BR, Reid JP. Perspective: Aerosol microphysics: From molecules to the chemical physics of aerosols. J Chem Phys 2017; 147:220901. [DOI: 10.1063/1.5002641] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Affiliation(s)
- Bryan R. Bzdek
- School of Chemistry, University of Bristol, Bristol BS8 1TS,
United Kingdom
| | - Jonathan P. Reid
- School of Chemistry, University of Bristol, Bristol BS8 1TS,
United Kingdom
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19
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Patel EH, Williams MA, Koehler SPK. Kinetic Energy and Angular Distributions of He and Ar Atoms Evaporating from Liquid Dodecane. J Phys Chem B 2017; 121:233-239. [PMID: 27997182 DOI: 10.1021/acs.jpcb.6b09994] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report both kinetic energy and angular distributions for He and Ar atoms evaporating from C12H26. All results were obtained by performing molecular dynamics simulations of liquid C12H26 with around 10-20 noble gas atoms dissolved in the liquid and by subsequently following the trajectories of the noble gas atoms after evaporation from the liquid. Whereas He evaporates with a kinetic energy distribution of (1.05 ± 0.03) × 2RT (corrected for the geometry used in experiments: (1.08 ± 0.03) × 2RT, experimentally obtained value: (1.14 ± 0.01) × 2RT), Ar displays a kinetic energy distribution that better matches a Maxwell-Boltzmann distribution at the temperature of the liquid ((0.99 ± 0.04) × 2RT). This behavior is also reflected in the angular distributions, which are close to a cosine distribution for Ar but slightly narrower, especially for faster atoms, in the case of He. This behavior of He is most likely due to the weak interaction potential between He and the liquid hydrocarbon.
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Affiliation(s)
| | | | - Sven P K Koehler
- Dalton Cumbrian Facility, The University of Manchester , Moor Row CA24 3HA, U.K
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20
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Ohoyama H, Teramoto T. Initial dissolution of D 2O at the gas-liquid interface of the ionic liquid [C 4min][NTf2] associated with hydrogen-bond network formation. Phys Chem Chem Phys 2016; 18:28061-28068. [PMID: 27711407 DOI: 10.1039/c6cp03448a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have studied the initial dissolution of D2O at the interfacial surface of the flowing jet sheet beam of the ionic liquid (IL) [C4min][NTf2] using the King and Wells method as a function of both the temperature and collision energy of the IL. The initial dissolution probability of D2O into the IL [C4min][NTf2] was found to follow the general propensity that the solubility of gases into a liquid decreases with temperature. However, a large partial molar enthalpy and entropy for the initial dissolution of D2O in the IL [C4min][NTf2] were observed from the temperature dependence of the initial dissolution probability: ΔHl = -53 ± 8 kJ mol-1, ΔSl = -210 ± 30 J mol-1 K-1. In addition, it was found that the collision energy significantly reduced the initial dissolution probability. We propose that the associated D2O molecules at the interface of the IL [C4min][NTf2] make a hydrogen-bond network around the [NTf2]- anion before dissolution into the deeper portion of the interface layer.
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Affiliation(s)
- H Ohoyama
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
| | - T Teramoto
- Department of Electrical & Electronic Engineering, College of Science & Engineering, Ritsumeikan University, Kusatsu, Shiga 525-8577, Japan
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21
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Bruggeman PJ, Kushner MJ, Locke BR, Gardeniers JGE, Graham WG, Graves DB, Hofman-Caris RCHM, Maric D, Reid JP, Ceriani E, Fernandez Rivas D, Foster JE, Garrick SC, Gorbanev Y, Hamaguchi S, Iza F, Jablonowski H, Klimova E, Kolb J, Krcma F, Lukes P, Machala Z, Marinov I, Mariotti D, Mededovic Thagard S, Minakata D, Neyts EC, Pawlat J, Petrovic ZL, Pflieger R, Reuter S, Schram DC, Schröter S, Shiraiwa M, Tarabová B, Tsai PA, Verlet JRR, von Woedtke T, Wilson KR, Yasui K, Zvereva G. Plasma–liquid interactions: a review and roadmap. ACTA ACUST UNITED AC 2016. [DOI: 10.1088/0963-0252/25/5/053002] [Citation(s) in RCA: 917] [Impact Index Per Article: 114.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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22
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Ando K, Arakawa M, Terasaki A. Evaporation Processes of a Liquid Droplet of Ethylene Glycol in a Vacuum. CHEM LETT 2016. [DOI: 10.1246/cl.160381] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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23
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Tesa-Serrate MA, Smoll EJ, Minton TK, McKendrick KG. Atomic and Molecular Collisions at Liquid Surfaces. Annu Rev Phys Chem 2016; 67:515-40. [PMID: 27090845 DOI: 10.1146/annurev-physchem-040215-112355] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The gas-liquid interface remains one of the least explored, but nevertheless most practically important, environments in which molecular collisions take place. These molecular-level processes underlie many bulk phenomena of fundamental and applied interest, spanning evaporation, respiration, multiphase catalysis, and atmospheric chemistry. We review here the research that has, during the past decade or so, been unraveling the molecular-level mechanisms of inelastic and reactive collisions at the gas-liquid interface. Armed with the knowledge that such collisions with the outer layers of the interfacial region can be unambiguously distinguished, we show that the scattering of gas-phase projectiles is a promising new tool for the interrogation of liquid surfaces with extreme surface sensitivity. Especially for reactive scattering, this method also offers absolute chemical selectivity for the groups that react to produce a specific observed product.
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Affiliation(s)
- Maria A Tesa-Serrate
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom;
| | - Eric J Smoll
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717;
| | - Timothy K Minton
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717;
| | - Kenneth G McKendrick
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom;
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24
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Tang M, Cziczo DJ, Grassian VH. Interactions of Water with Mineral Dust Aerosol: Water Adsorption, Hygroscopicity, Cloud Condensation, and Ice Nucleation. Chem Rev 2016; 116:4205-59. [DOI: 10.1021/acs.chemrev.5b00529] [Citation(s) in RCA: 228] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mingjin Tang
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Daniel J. Cziczo
- Department
of Earth, Atmospheric and Planetary Sciences and Civil and Environmental
Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Vicki H. Grassian
- Department
of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
- Departments
of Chemistry and Biochemistry, Nanoengineering and Scripps Institution
of Oceanography, University of California San Diego, La Jolla, California 92093, United States
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25
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Faust JA, Sobyra TB, Nathanson GM. Gas-Microjet Reactive Scattering: Collisions of HCl and DCl with Cool Salty Water. J Phys Chem Lett 2016; 7:730-735. [PMID: 26828574 DOI: 10.1021/acs.jpclett.5b02848] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Liquid microjets provide a powerful means to investigate reactions of gases with salty water in vacuum while minimizing gas-vapor collisions. We use this technique to explore the fate of gaseous HCl and DCl molecules impinging on 8 molal LiCl and LiBr solutions at 238 K. The experiments reveal that HCl or DCl evaporate infrequently if they become thermally accommodated at the surface of either solution. In particular, we observe minimal thermal desorption of HCl following HCl collisions and no distinct evidence for rapid, interfacial DCl→HCl exchange following DCl collisions. These results imply that surface thermal motions are not generally strong enough to propel momentarily trapped HCl or DCl back into the gas phase before they ionize and disappear into solution. Instead, only HCl and DCl molecules that scatter directly from the surface escape entry. These recoiling molecules transfer less energy upon collision to LiBr/H2O than to LiCl/H2O, reflecting the heavier mass of Br(-) than of Cl(-) in the interfacial region.
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Affiliation(s)
- Jennifer A Faust
- Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
| | - Thomas B Sobyra
- Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
| | - Gilbert M Nathanson
- Department of Chemistry, University of Wisconsin-Madison , 1101 University Avenue, Madison, Wisconsin 53706-1322, United States
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26
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Murdachaew G, Nathanson GM, Benny Gerber R, Halonen L. Deprotonation of formic acid in collisions with a liquid water surface studied by molecular dynamics and metadynamics simulations. Phys Chem Chem Phys 2016; 18:29756-29770. [DOI: 10.1039/c6cp06071d] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Formic acid has a lower barrier to deprotonation at the air–water interface than in bulk liquid water.
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Affiliation(s)
- Garold Murdachaew
- Laboratory of Physical Chemistry
- Department of Chemistry
- FI-00014 University of Helsinki
- Finland
| | | | - R. Benny Gerber
- Laboratory of Physical Chemistry
- Department of Chemistry
- FI-00014 University of Helsinki
- Finland
- Institute of Chemistry and the Fritz Haber Research Center
| | - Lauri Halonen
- Laboratory of Physical Chemistry
- Department of Chemistry
- FI-00014 University of Helsinki
- Finland
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27
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Faust JA, Nathanson GM. Microjets and coated wheels: versatile tools for exploring collisions and reactions at gas–liquid interfaces. Chem Soc Rev 2016; 45:3609-20. [DOI: 10.1039/c6cs00079g] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Scattering experiments using liquid microjets provide a window into collisions and reactions at the surfaces of high vapor pressure liquids.
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28
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Partanen L, Murdachaew G, Gerber RB, Halonen L. Temperature and collision energy effects on dissociation of hydrochloric acid on water surfaces. Phys Chem Chem Phys 2016; 18:13432-42. [DOI: 10.1039/c6cp00597g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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29
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Pozniak BP, Cole RB. Perspective on electrospray ionization and its relation to electrochemistry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2015; 26:369-385. [PMID: 25623197 DOI: 10.1007/s13361-014-1066-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 12/08/2014] [Accepted: 12/11/2014] [Indexed: 06/04/2023]
Abstract
The phenomenon of electrospraying of liquids is presented from the perspective of the electrochemistry involved. Basics of current and liquid flow in the capillary and spray tip are discussed, followed by specifics of charging and discharging of the sprayed liquid surface. Fundamental theories and numerical modeling relating electrospray current to solution and spray parameters are described and then compared with our own experimentally obtained data. The method of mapping potentials and currents inside the electrospray capillary by using an inserted electrically-isolated small wire probe electrode is discussed in detail with illustrations from new and published data. Based on these experimentally obtained results, a new mathematical model is derived. The introduced "nonlinear resistor electrospray capillary model" divides the electrospray capillary into small sections, adds their contributions, and then, by transition to infinitely small section thickness, produces analytical formulas that relate current and potential maps to other properties of the electrospraying liquid: primarily conductivity and current density. The presentation of the model is undertaken from an elementary standpoint, and it offers the possibility to obtain quantitative information regarding operating parameters from typical analytical systems subjected to electrospray. The model stresses simplicity and ease of use; examples applying experimental data are shown and some predictions of the model are also presented. The developed nonlinear resistor electrospray capillary model is intended to provide a new quantitative basis for improving the understanding of electrochemical transformations occurring in the electrospray emitter. A supplemental material section gives full derivation of the model and discusses other consequences.
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Affiliation(s)
- Boguslaw P Pozniak
- Department of Chemistry, University of New Orleans, 2000 Lakeshore Dr., New Orleans, LA, 70148, USA
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30
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Houle FA, Hinsberg WD, Wilson KR. Oxidation of a model alkane aerosol by OH radical: the emergent nature of reactive uptake. Phys Chem Chem Phys 2015; 17:4412-23. [DOI: 10.1039/c4cp05093b] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reactive uptake of OH by organic aerosol particles is situational and related to internal diffusion distances between OH sticking events.
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Affiliation(s)
- F. A. Houle
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
| | | | - K. R. Wilson
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
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31
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Johnson AM, Lancaster DK, Faust JA, Hahn C, Reznickova A, Nathanson GM. Ballistic Evaporation and Solvation of Helium Atoms at the Surfaces of Protic and Hydrocarbon Liquids. J Phys Chem Lett 2014; 5:3914-3918. [PMID: 26278769 DOI: 10.1021/jz501987r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Atomic and molecular solutes evaporate and dissolve by traversing an atomically thin boundary separating liquid and gas. Most solutes spend only short times in this interfacial region, making them difficult to observe. Experiments that monitor the velocities of evaporating species, however, can capture their final interactions with surface solvent molecules. We find that polarizable gases such as N2 and Ar evaporate from protic and hydrocarbon liquids with Maxwell-Boltzmann speed distributions. Surprisingly, the weakly interacting helium atom emerges from these liquids at high kinetic energies, exceeding the expected energy of evaporation from salty water by 70%. This super-Maxwellian evaporation implies in reverse that He atoms preferentially dissolve when they strike the surface at high energies, as if ballistically penetrating into the solvent. The evaporation energies increase with solvent surface tension, suggesting that He atoms require extra kinetic energy to navigate increasingly tortuous paths between surface molecules.
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Affiliation(s)
- Alexis M Johnson
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Diane K Lancaster
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Jennifer A Faust
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Christine Hahn
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Anna Reznickova
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Gilbert M Nathanson
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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32
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Popolan-Vaida DM, Wilson KR, Leone SR. Reaction of Iodine Atoms with Submicrometer Squalane and Squalene Droplets: Mechanistic Insights into Heterogeneous Reactions. J Phys Chem A 2014; 118:10688-98. [DOI: 10.1021/jp5085247] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Denisia M. Popolan-Vaida
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
| | - Kevin R. Wilson
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Stephen R. Leone
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Department
of Physics, University of California, Berkeley, California 94720, United States
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33
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Andersson G, Ridings C. Ion Scattering Studies of Molecular Structure at Liquid Surfaces with Applications in Industrial and Biological Systems. Chem Rev 2014; 114:8361-87. [DOI: 10.1021/cr400417f] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Gunther Andersson
- Centre
for NanoScale Science
and Technology, Flinders University, Adelaide, South Australia 5001, Australia
| | - Christiaan Ridings
- Centre
for NanoScale Science
and Technology, Flinders University, Adelaide, South Australia 5001, Australia
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34
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Burden DK, Johnson AM, Krier JM, Nathanson GM. The Entry of HCl through Soluble Surfactants on Sulfuric Acid: Effects of Chain Branching. J Phys Chem B 2014; 118:7993-8001. [DOI: 10.1021/jp501080g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daniel K. Burden
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Alexis M. Johnson
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - James M. Krier
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Gilbert M. Nathanson
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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35
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Hama T, Watanabe N. Surface Processes on Interstellar Amorphous Solid Water: Adsorption, Diffusion, Tunneling Reactions, and Nuclear-Spin Conversion. Chem Rev 2013; 113:8783-839. [DOI: 10.1021/cr4000978] [Citation(s) in RCA: 211] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tetsuya Hama
- Institute of Low Temperature
Science, Hokkaido University, N19W8 Kita-ku, Sapporo, Hokkaido 060-0819, Japan
| | - Naoki Watanabe
- Institute of Low Temperature
Science, Hokkaido University, N19W8 Kita-ku, Sapporo, Hokkaido 060-0819, Japan
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36
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Flannigan DJ, Suslick KS. Non-Boltzmann Population Distributions during Single-Bubble Sonoluminescence. J Phys Chem B 2013; 117:15886-93. [DOI: 10.1021/jp409222x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- David J. Flannigan
- Department of Chemical
Engineering and Materials Science, University of Minnesota, 421 Washington
Avenue SE, Minneapolis, Minnesota 55455, United States
| | - Kenneth S. Suslick
- Department of Chemistry, University of Illinois at Urbana−Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
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37
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Alexander WA, Zhang J, Murray VJ, Nathanson GM, Minton TK. Kinematics and dynamics of atomic-beam scattering on liquid and self-assembled monolayer surfaces. Faraday Discuss 2013; 157:355-74; discussion 375-98. [PMID: 23230778 DOI: 10.1039/c2fd20034a] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have conducted investigations of the energy transfer dynamics of atomic oxygen and argon scattering from hydrocarbon and fluorocarbon surfaces. In light of these results, we appraise the applicability and value of a kinematic scattering model, which views a gas-surface interaction as a gas-phase-like collision between an incident atom or molecule and a localized region of the surface with an effective mass. We have applied this model to interpret the effective surface mass and energy transfer when atoms strike two different surfaces under identical bombardment conditions. To this end, we have collected new data, and we have re-examined existing data sets from both molecular-beam experiments and molecular dynamics simulations. We seek to identify trends that could lead to a robust general understanding of energy transfer processes induced by collisions of gas-phase species with liquid and semi-solid surfaces.
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Affiliation(s)
- William A Alexander
- Department of Chemistry and Biochemistry, Montana State University, 103 Chem/Biochem Bldg., Bozeman, MT 59717, USA
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Influence of organic films on the evaporation and condensation of water in aerosol. Proc Natl Acad Sci U S A 2013; 110:8807-12. [PMID: 23674675 DOI: 10.1073/pnas.1305277110] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Uncertainties in quantifying the kinetics of evaporation and condensation of water from atmospheric aerosol are a significant contributor to the uncertainty in predicting cloud droplet number and the indirect effect of aerosols on climate. The influence of aerosol particle surface composition, particularly the impact of surface active organic films, on the condensation and evaporation coefficients remains ambiguous. Here, we report measurements of the influence of organic films on the evaporation and condensation of water from aerosol particles. Significant reductions in the evaporation coefficient are shown to result when condensed films are formed by monolayers of long-chain alcohols [C(n)H(2n+1)OH], with the value decreasing from 2.4 × 10(-3) to 1.7 × 10(-5) as n increases from 12 to 17. Temperature-dependent measurements confirm that a condensed film of long-range order must be formed to suppress the evaporation coefficient below 0.05. The condensation of water on a droplet coated in a condensed film is shown to be fast, with strong coherence of the long-chain alcohol molecules leading to islanding as the water droplet grows, opening up broad areas of uncoated surface on which water can condense rapidly. We conclude that multicomponent composition of organic films on the surface of atmospheric aerosol particles is likely to preclude the formation of condensed films and that the kinetics of water condensation during the activation of aerosol to form cloud droplets is likely to remain rapid.
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King KL, Paterson G, Rossi GE, Iljina M, Westacott RE, Costen ML, McKendrick KG. Inelastic scattering of OH radicals from organic liquids: isolating the thermal desorption channel. Phys Chem Chem Phys 2013; 15:12852-63. [DOI: 10.1039/c3cp51708j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Flannigan DJ, Suslick KS. Temperature Nonequilibration during Single-Bubble Sonoluminescence. J Phys Chem Lett 2012; 3:2401-2404. [PMID: 26292122 DOI: 10.1021/jz301100j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Single-bubble sonoluminescence (SBSL) spectra from liquids having low vapor pressures, especially mineral acids, are exceptionally rich. During SBSL from aqueous sulfuric acid containing dissolved neon, rovibronic emission spectra reveal vibrationally hot sulfur monoxide (SO; Tv = 2100 K) that is also rotationally cold (Tr = 290 K). In addition to SO, excited neon atom emission gives an estimated temperature, for neon, of several thousand Kelvin. This nonequilibrated temperature is consistent with dynamically constrained SO formation at the liquid-vapor interface of the collapsing bubble. Formation occurs via collisions of fast neon atoms (generated within the collapsing bubble) with liquid-phase molecular species in the interfacial region, thus allowing for a mechanistic understanding of the processes leading to light emission.
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Affiliation(s)
- David J Flannigan
- †Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington Avenue Southeast, Minneapolis, Minnesota 55455, United States
| | - Kenneth S Suslick
- ‡Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
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Abstract
For more than two decades a cadre of physical chemists has focused on understanding the formation processes, chemical composition, and chemical kinetics of atmospheric aerosol particles and droplets with diameters ranging from a few nanometers to ∼10,000 nm. They have adapted or invented a range of fundamental experimental and theoretical tools to investigate the thermochemistry, mass transport, and chemical kinetics of processes occurring at nanoscale gas-liquid and gas-solid interfaces for a wide range of nonideal, real-world substances. State-of-the-art laboratory methods devised to study molecular spectroscopy, chemical kinetics, and molecular dynamics also have been incorporated into field measurement instruments that are deployed routinely on research aircraft, ships, and mobile laboratories as well as at field sites from megacities to the most remote jungle, desert, and polar locations. These instruments can now provide real-time, size-resolved aerosol particle physical property and chemical composition data anywhere in Earth's troposphere and lower stratosphere.
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Affiliation(s)
| | - Douglas R. Worsnop
- Center for Aerosol and Cloud Chemistry, Aerodyne Research, Inc., Billerica, Massachusetts 01821-3976
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Lovelock KRJ. Influence of the ionic liquid/gas surface on ionic liquid chemistry. Phys Chem Chem Phys 2012; 14:5071-89. [PMID: 22349469 DOI: 10.1039/c2cp23851a] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Applications such as gas storage, gas separation, NP synthesis and supported ionic liquid phase catalysis depend upon the interaction of different species with the ionic liquid/gas surface. Consequently, these applications cannot proceed to the full extent of their potential without a profound understanding of the surface structure and properties. As a whole, this perspective contains more questions than answers, which demonstrates the current state of the field. Throughout this perspective, crucial questions are posed and a roadmap is proposed to answer these questions. A critical analysis is made of the field of ionic liquid/gas surface structure and properties, and a number of design rules are mined. The effects of ionic additives on the ionic liquid/gas surface structure are presented. A possible driving force for surface formation is discussed that has, to the best of my knowledge, not been postulated in the literature to date. This driving force suggests that for systems composed solely of ions, the rules for surface formation of dilute electrolytes do not apply. The interaction of neutral additives with the ionic liquid/gas surface is discussed. Particular attention is focussed upon H(2)O and CO(2), vital additives for many applications of ionic liquids. Correlations between ionic liquid/gas surface structure and properties, ionic liquid surfaces plus additives, and ionic liquid applications are given.
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Affiliation(s)
- Kevin R J Lovelock
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK.
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Roscioli JR, Bell DJ, Nelson DJ, Nesbitt DJ. State-resolved velocity map imaging of surface-scattered molecular flux. Phys Chem Chem Phys 2012; 14:4070-80. [DOI: 10.1039/c1cp22938a] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Gisler AW, Nesbitt DJ. On probing ions at the gas–liquid interface by quantum state-resolved molecular beam scattering: the curious incident of the cation in the night time. Faraday Discuss 2012; 157:297-305; discussion 375-98. [PMID: 23230774 DOI: 10.1039/c2fd20026k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Andrew W Gisler
- National Institute of Standards and Technology, Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0440, USA
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Hazra MK, Sinha A. Formic Acid Catalyzed Hydrolysis of SO3 in the Gas Phase: A Barrierless Mechanism for Sulfuric Acid Production of Potential Atmospheric Importance. J Am Chem Soc 2011; 133:17444-53. [DOI: 10.1021/ja207393v] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Montu K. Hazra
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0314, United States
| | - Amitabha Sinha
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0314, United States
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Roscioli JR, Nesbitt DJ. Quantum State Resolved Scattering from Room-Temperature Ionic Liquids: The Role of Cation versus Anion Structure at the Interface. J Phys Chem A 2011; 115:9764-73. [DOI: 10.1021/jp2033802] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joseph R. Roscioli
- JILA, University of Colorado and National Institute of Standards and Technology, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0440, United States
| | - David J. Nesbitt
- JILA, University of Colorado and National Institute of Standards and Technology, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0440, United States
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Vehmanen E, Ghazarian V, Sams C, Khachatryan I, Eloranta J, Apkarian VA. Injection of atoms and molecules in a superfluid helium fountain: Cu and Cu2He(n) (n = 1, ..., ∞). J Phys Chem A 2011; 115:7077-88. [PMID: 21449544 DOI: 10.1021/jp1123986] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We introduce an experimental platform designed around a thermomechanical helium fountain, which is aimed at investigating spectroscopy and dynamics of atoms and molecules in the superfluid and at its vapor interface. Laser ablation of copper, efficient cooling and transport of Cu and Cu(2) through helium vapor (1.5 K < T < 20 K), formation of linear and T-shaped Cu(2)-He complexes, and their continuous evolution into large Cu(2)-He(n) clusters and droplets are among the processes that are illustrated. Reflection is the dominant quantum scattering channel of translationally cold copper atoms (T = 1.7 K) at the fountain interface. Cu(2) dimers mainly travel through the fountain unimpeded. However, the conditions of fountain flow and transport of molecules can be controlled to demonstrate injection and, in particular, injection into a nondivergent columnar fountain with a plug velocity of about 1 m/s. The experimental observables are interpreted with the aid of bosonic density functional theory calculations and ab initio interaction potentials.
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Affiliation(s)
- Esa Vehmanen
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, FIN 40014, Finland
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Desai TV, Hong S, Woll AR, Hughes KJ, Kaushik AP, Clancy P, Engstrom JR. Hyperthermal organic thin film growth on surfaces terminated with self-assembled monolayers. I. The dynamics of trapping. J Chem Phys 2011; 134:224702. [DOI: 10.1063/1.3591965] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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50
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Ota ST, Richmond GL. Chilling out: a cool aqueous environment promotes the formation of gas-surface complexes. J Am Chem Soc 2011; 133:7497-508. [PMID: 21520889 DOI: 10.1021/ja201027k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
SO(2), an important atmospheric pollutant, has been implicated in environmental phenomena such as acid rain, climate change, and cloud formation. In addition, SO(2) is fundamentally interesting because it forms spectroscopically identifiable complexes with water at aqueous surfaces. Vibrational sum frequency spectroscopy (VSFS) is used here to further investigate the mechanism by which SO(2) adsorbs to water at tropospherically relevant temperatures (0-23 °C). The spectral results lead to two important conclusions. SO(2) surface affinity is enhanced at colder temperatures, with nearly all of the topmost water molecules showing evidence of binding to SO(2) at 0 °C as compared to a much lower fraction at room temperature. This surface adsorption results in significant changes in water orientation at the surface, but is reversible at the temperatures examined here. Second, the SO(2) complex formation at aqueous surfaces is independent of aqueous solution acidity. One challenge in previous uptake studies was the ability to distinguish between the effects of surface adsorption as compared to bulk accommodation. The surface and vibrational specificity of these studies make this distinction possible, allowing a selective study of how the aqueous properties temperature and pH influence SO(2) surface affinity.
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Affiliation(s)
- Stephanie T Ota
- Department of Chemistry, University of Oregon, Eugene, Oregon 97403, USA
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