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Smith RS, Yuan C, Petrik NG, Kimmel GA, Kay BD. Crystallization growth rates and front propagation in amorphous solid water films. J Chem Phys 2019; 150:214703. [DOI: 10.1063/1.5098481] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- R. Scott Smith
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Chunqing Yuan
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Nikolay G. Petrik
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Greg A. Kimmel
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Bruce D. Kay
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
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Smith RS, Petrik NG, Kimmel GA, Kay BD. Communication: Proton exchange in low temperature co-mixed amorphous H 2O and D 2O films: The effect of the underlying Pt(111) and graphene substrates. J Chem Phys 2018; 149:081104. [PMID: 30193464 DOI: 10.1063/1.5046530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Isotopic exchange reactions in mixed D2O and H2O amorphous solid water (ASW) films were investigated using reflection absorption infrared spectroscopy. Nanoscale films composed of 5% D2O in H2O were deposited on Pt(111) and graphene covered Pt(111) substrates. At 130 K, we find that the reaction is strongly dependent on the substrate with the H/D exchange being significantly more rapid on the Pt(111) surface than on graphene. At 140 K, the films eventually crystallize with the final products on the two substrates being primarily HOD molecule on Pt(111) and a mixture of HOD and unreacted D2O on graphene. We demonstrate by pre-dosing H2 and O2 on Pt(111) that the observed differences in reactivity on the two substrates are likely due to the formation of hydrogen ions at the Pt(111) surface that are not formed on graphene. Once formed the mobile protons move through the ASW overlayer to initiate the H/D exchange reaction.
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Affiliation(s)
- R Scott Smith
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Nikolay G Petrik
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Greg A Kimmel
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Bruce D Kay
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
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Yuan C, Smith RS, Kay BD. Communication: Distinguishing between bulk and interface-enhanced crystallization in nanoscale films of amorphous solid water. J Chem Phys 2017; 146:031102. [DOI: 10.1063/1.4974492] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Chunqing Yuan
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - R. Scott Smith
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
| | - Bruce D. Kay
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
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Woon DE. Quantum chemical protocols for modeling reactions and spectra in astrophysical ice analogs: the challenging case of the C⁺ + H₂O reaction in icy grain mantles. Phys Chem Chem Phys 2015; 17:28705-18. [PMID: 26445904 DOI: 10.1039/c5cp03393d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Icy grain mantles that accrete on refractory dust particles in the very cold interstellar medium or beyond the snow line in protoplanetary disks serve as minute incubators for heterogeneous chemistry. Ice mantle chemistry can differ significantly from the gas phase chemistry that occurs in these environments and is often richer. Modeling ices and their chemistry is a challenging task for quantum theoretical methods, but theory promises insight into these systems that is difficult to attain with experiments. Density functional theory (DFT) is predominately employed for modeling reactions in icy grain mantles due to its favorable scalability, but DFT has limitations that risk undercutting its reliability for this task. In this work, basic protocols are proposed for identifying the degree to which DFT methods are able to reproduce experimental or higher level theoretical results for the fundamental interactions upon which ice mantle chemistry depends, including both reactive interactions and non-reactive scaffolding interactions. The exemplar of this study is the reaction of C(+) with H2O, where substantial methodological differences are found in the prediction of gas phase relative energetics for stationary points (about 10 kcal mol(-1) for the C-O bond energy of the H2OC(+) intermediate), which in turn casts doubt about employing it to treat the C(+) + H2O reaction on an ice surface. However, careful explorations demonstrate that B3LYP with small correlation consistent basis sets performs in a sufficiently reliable manner to justify using it to identify plausible chemical pathways, where the dominant products were found to be neutral HOC and the CO(-) anion plus one and two H3O(+) cations, respectively. Predicted vibrational and electronic spectra are presented that would serve to verify or disconfirm the pathways; the latter were computed with time-dependent DFT. Conclusions are compared with those of a recent similar study by McBride and coworkers (J. Phys. Chem. A, 2014, 118, 6991).
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Affiliation(s)
- David E Woon
- Department of Chemistry, University of Illinois at Urbana-Champaign, Box 92-6, CLSL, 600 S. Mathews, Urbana, IL 61801, USA.
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Isenor M, Signorell R. Infrared spectroscopy of solid mixed ammonia–water and acetylene–water aerosol particles. Mol Phys 2014. [DOI: 10.1080/00268976.2014.981232] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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McCartney SA, Sadtchenko V. Fast scanning calorimetry studies of the glass transition in doped amorphous solid water: Evidence for the existence of a unique vicinal phase. J Chem Phys 2013; 138:084501. [DOI: 10.1063/1.4789629] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Liu H, Wang Y, Bowman JM. Quantum Calculations of Intramolecular IR Spectra of Ice Models Using Ab Initio Potential and Dipole Moment Surfaces. J Phys Chem Lett 2012; 3:3671-3676. [PMID: 26291094 DOI: 10.1021/jz3016777] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report the IR spectra of two forms of ice in the monomer bend and OH-stretching regions, using recently developed ab initio potential and dipole moment surfaces for arbitrarily many water monomers. Coupling and anharmonicity of the intramolecular vibrational modes are taken into account using coupled three-mode variational calculations, within the local-monomer model. Spectra for the surface and core regions of these ice models are presented. The calculated spectra for the core region, with no adjustments, are in good agreement with experiment for the intramolecular OH-stretch and bend regions. Our analysis also shows a significant contribution from the overtone of the monomer bend to the OH-stretch region of the spectra.
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Affiliation(s)
- Hanchao Liu
- Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Yimin Wang
- Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
| | - Joel M Bowman
- Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States
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Smith RS, Petrik NG, Kimmel GA, Kay BD. Thermal and nonthermal physiochemical processes in nanoscale films of amorphous solid water. Acc Chem Res 2012; 45:33-42. [PMID: 21627126 DOI: 10.1021/ar200070w] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Amorphous solid water (ASW) is a disordered version of ice created by vapor deposition onto a cold substrate (typically less than 130 K). It has a higher free energy than the crystalline phase of ice, and when heated above its glass transition temperature, it transforms into a metastable supercooled liquid. This unusual form of water exists on earth only in laboratories, after preparation with highly specialized equipment. It is thus fair to ask why there is any interest in studying such an esoteric material. Much of the scientific interest results from the ability to use ASW as a model system for exploring the physical and reactive properties of liquid water and aqueous solutions. ASW is also thought to be the predominant form of water in the extremely cold temperatures of many interstellar and planetary environments. In addition, ASW is a convenient model system for studying the stability of amorphous and glassy materials as well as the properties of highly porous materials. A fundamental understanding of such properties is invaluable in a diverse range of applications, including cryobiology, food science, pharmaceuticals, astrophysics, and nuclear waste storage, among others. Over the past 15 years, we have used molecular beams and surface science techniques to probe the thermal and nonthermal properties of nanoscale films of ASW. In this Account, we present a survey of our research on the properties of ASW using this approach. We use molecular beams to precisely control the deposition conditions (flux, incident energy, and incident angle) and create compositionally tailored, nanoscale films of ASW at low temperatures. To study the transport properties (viscosity and diffusivity), we heat the amorphous films above their glass transition temperature, T(g), at which they transform into deeply supercooled liquids prior to crystallization. The advantage of this approach is that at temperatures near T(g), the viscosity is approximately 15 orders of magnitude larger than that of a normal liquid. As a result, the crystallization kinetics are dramatically slowed, increasing the time available for experiments. For example, near T(g), a water molecule moves less than the distance of a single molecule on a typical laboratory time scale (∼1000 s). For this reason, nanoscale films help to probe the behavior and reactions of supercooled liquids at these low temperatures. ASW films can also be used for investigating the nonthermal reactions relevant to radiolysis.
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Affiliation(s)
- R. Scott Smith
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland, Washington 99352, United States
| | - Nikolay G. Petrik
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland, Washington 99352, United States
| | - Greg A. Kimmel
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland, Washington 99352, United States
| | - Bruce D. Kay
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland, Washington 99352, United States
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Bhattacharya D, Payne CN, Sadtchenko V. Bulk and Interfacial Glass Transitions of Water. J Phys Chem A 2011; 115:5965-72. [DOI: 10.1021/jp110372t] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Candace N. Payne
- Department of Chemistry, The George Washington University, Washington, DC 20052
| | - Vlad Sadtchenko
- Department of Chemistry, The George Washington University, Washington, DC 20052
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Smith RS, Matthiesen J, Knox J, Kay BD. Crystallization Kinetics and Excess Free Energy of H2O and D2O Nanoscale Films of Amorphous Solid Water. J Phys Chem A 2011; 115:5908-17. [DOI: 10.1021/jp110297q] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- R. Scott Smith
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland Washington 99352, United States
| | - Jesper Matthiesen
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland Washington 99352, United States
| | - Jake Knox
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland Washington 99352, United States
| | - Bruce D. Kay
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland Washington 99352, United States
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May RA, Smith RS, Kay BD. Probing the interaction of amorphous solid water on a hydrophobic surface: dewetting and crystallization kinetics of ASW on carbon tetrachloride. Phys Chem Chem Phys 2011; 13:19848-55. [DOI: 10.1039/c1cp21855g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Mitterdorfer C, Bauer M, Loerting T. Clathrate hydrate formation after CO2–H2O vapour deposition. Phys Chem Chem Phys 2011; 13:19765-72. [DOI: 10.1039/c1cp21856e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Smith RS, Zubkov T, Dohnálek Z, Kay BD. The Effect of the Incident Collision Energy on the Porosity of Vapor-Deposited Amorphous Solid Water Films. J Phys Chem B 2008; 113:4000-7. [DOI: 10.1021/jp804902p] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- R. Scott Smith
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland Washington 99352
| | - Tykhon Zubkov
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland Washington 99352
| | - Zdenek Dohnálek
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland Washington 99352
| | - Bruce D. Kay
- Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, P.O. Box 999, Mail Stop K8-88, Richland Washington 99352
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Fanourgakis GS, Xantheas SS. Development of transferable interaction potentials for water. V. Extension of the flexible, polarizable, Thole-type model potential (TTM3-F, v. 3.0) to describe the vibrational spectra of water clusters and liquid water. J Chem Phys 2008; 128:074506. [DOI: 10.1063/1.2837299] [Citation(s) in RCA: 313] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Jagoda-Cwiklik B, Devlin JP, Buch V. Spectroscopic and computational evidence for SO2 ionization on 128 K ice surface. Phys Chem Chem Phys 2008; 10:4678-84. [DOI: 10.1039/b809839p] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Kondo T, Kato HS, Kawai M, Bonn M. The distinct vibrational signature of grain-boundary water in nano-crystalline ice films. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.09.068] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kondo T, Kato HS, Bonn M, Kawai M. Deposition and crystallization studies of thin amorphous solid water films on Ru(0001) and on CO-precovered Ru(0001). J Chem Phys 2007; 127:094703. [PMID: 17824755 DOI: 10.1063/1.2770726] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
The deposition and the isothermal crystallization kinetics of thin amorphous solid water (ASW) films on both Ru(0001) and CO-precovered Ru(0001) have been investigated in real time by simultaneously employing helium atom scattering, infrared reflection absorption spectroscopy, and isothermal temperature-programmed desorption. During ASW deposition, the interaction between water and the substrate depends critically on the amount of preadsorbed CO. However, the mechanism and kinetics of the crystallization of approximately 50 layers thick ASW film were found to be independent of the amount of preadsorbed CO. We demonstrate that crystallization occurs through random nucleation events in the bulk of the material, followed by homogeneous growth, for solid water on both substrates. The morphological change involving the formation of three-dimensional grains of crystalline ice results in the exposure of the water monolayer just above the substrate to the vacuum during the crystallization process on both substrates.
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Affiliation(s)
- Takahiro Kondo
- Institute of material science, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8573 Japan.
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Kondo T, Kato HS, Bonn M, Kawai M. Morphological change during crystallization of thin amorphous solid water films on Ru(0001). J Chem Phys 2007; 126:181103. [PMID: 17508785 DOI: 10.1063/1.2739504] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The isothermal crystallization process of thin amorphous solid water (ASW) films on Ru(0001) has been investigated in real time by simultaneously employing helium atom scattering, infrared reflection absorption spectroscopy, and isothermal temperature-programmed desorption. The measurements reveal that the crystallization mechanism consists of random nucleation events in the bulk of the ASW films, followed by homogeneous growth. Morphological changes of the solid water film during crystallization expose the water monolayer just above the substrate to the vacuum during the crystallization process.
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Affiliation(s)
- Takahiro Kondo
- Surface Chemistry Laboratory, RIKEN (The Institute of Physical and Chemical Research), 2-1-1 Wako, Hirosawa, Saitama 351-0198, Japan
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Beniya A, Yamamoto S, Mukai K, Yamashita Y, Yoshinobu J. The first layer of water on Rh(111): Microscopic structure and desorption kinetics. J Chem Phys 2006; 125:054717. [PMID: 16942251 DOI: 10.1063/1.2227393] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The adsorption states and growth process of the first water (D2O) layer on Rh(111) were investigated using infrared reflection absorption spectroscopy, temperature programed desorption, and spot-profile-analysis low energy electron diffraction. Water molecules wet the Rh(111) surface intact. At the early stage of first layer growth, a (square root 3 x square root 3)R30 degrees commensurate water layer grows where "up" and "down" species coexist; the up and down species represent water molecules which have free OD, pointing to a vacuum and the substrate, respectively. The up domain was a flatter structure than an icelike bilayer. Water desorption from Rh(111) was a half-order process. The activation energy and the preexponential factor of desorption are estimated to be 60 kJ/mol and 4.8 x 10(16) ML(1/2)/s at submonolayer coverage, respectively. With an increase in water coverage, the flat up domain becomes a zigzag layer, like an ice bilayer. At the saturation coverage, the amount of down species is 1.3 times larger than that of the up species. In addition, the activation energy and the preexponential factor of desorption decrease to 51 kJ/mol and 1.3 x 10(14) ML(1/2)/s, respectively.
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Affiliation(s)
- Atsushi Beniya
- The Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan
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Scott Smith R, Zubkov T, Kay BD. The effect of the incident collision energy on the phase and crystallization kinetics of vapor deposited water films. J Chem Phys 2006; 124:114710. [PMID: 16555913 DOI: 10.1063/1.2177658] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Molecular beam techniques are used to grow water films on Pt(111) with incident collision energies from 5 to 205 kJ/mole. The effect of the incident collision energy on the phase of vapor deposited water films and their subsequent crystallization kinetics are studied using temperature programmed desorption and infrared spectroscopy. We find that for films deposited at substrate temperatures below 110 K, the incident kinetic energy (up to 205 kJ/mole) has no effect on the initial phase of the deposited film or its crystallization kinetics. Above 110 K, the substrate temperature does affect the phase and crystallization kinetics of the deposited films but this result is also independent of the incident collision energy. The presence of a crystalline ice template (underlayer) does affect the crystallization of amorphous solid water, but this effect is also independent of the incident beam energy. These results suggest that the crystallization of amorphous solid water requires cooperative motion of several water molecules.
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Affiliation(s)
- R Scott Smith
- Fundamental Science Directorate, Pacific Northwest National Laboratory, Richland, Washington 99352, USA
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Fanourgakis GS, Aprà E, de Jong WA, Xantheas SS. High-level ab initio calculations for the four low-lying families of minima of(H2O)20. II. Spectroscopic signatures of the dodecahedron, fused cubes, face-sharing pentagonal prisms, and edge-sharing pentagonal prisms hydrogen bonding networks. J Chem Phys 2005; 122:134304. [PMID: 15847462 DOI: 10.1063/1.1864892] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report the first harmonic vibrational spectra for each of the lowest lying isomers within the four major families of minima of (H2O)20, namely, the dodecahedron, fused cubes, face-sharing pentagonal prisms, and edge-sharing pentagonal prisms. These were obtained at the second-order Moller-Plesset perturbation level of theory (MP2) with the augmented correlation consistent basis set of double zeta quality (aug-cc-pVDZ) at the corresponding minimum energy geometries. The computed infrared (IR) spectra are the first ones obtained from first principles for these clusters. They were found to contain spectral features, which can be directly mapped onto the distinctive spectroscopic signatures of their constituent tetramer, pentamer, and octamer fragments. The dodecahedron spectra show the richest structure in the OH stretching region and are associated with the most redshifted OH vibrations with respect to the monomer. The lowest lying edge-sharing pentagonal prism isomer displays intense IR active vibrations that are redshifted by approximately 600 cm(-1) with respect to the water monomer. Furthermore the most redshifted, IR-active OH stretching vibrations for all four networks correspond to hydrogen bonded OH groups, which exhibit the following two common characteristics: (i) they belong to fragments which have a "free" OH stretch and (ii) they act as donors to a neighboring water molecule along a "dimerlike" (strong) hydrogen bond. The zero-point energy corrected MP2/CBS (complete basis set) limit binding energies D(0) for the four isomers are -163.1 kcal/mol (edge-sharing pentagonal prism), -160.1 kcal/mol (face-sharing pentagonal prism), -157.5 kcal/mol (fused cubes), and -148.1 kcal/mol (dodecahedron).
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Affiliation(s)
- George S Fanourgakis
- Chemical Sciences Division, Pacific Northwest National Laboratory, MS K1-83 Richland, WA 99352, USA
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