1
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Deal A, Smith AE, Oyala KM, Campolo GH, Rugeley BE, Mose TA, Talley DL, Cooley CB, Rapf RJ. Infrared Reflection-Absorption Spectroscopy of α-Keto Acids at the Air-Water Interface: Effects of Chain Length and Headgroup on Environmentally Relevant Surfactant Films. J Phys Chem A 2023; 127:4137-4151. [PMID: 37103984 PMCID: PMC10184673 DOI: 10.1021/acs.jpca.3c01266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 04/12/2023] [Indexed: 04/28/2023]
Abstract
A variety of organic surfactants are found at air-water interfaces in natural environments, including on the surfaces of aqueous aerosols. The structure and morphology of these organic films can have profound impacts on material transfer between the gas and condensed phases, the optical properties of atmospheric aerosol, and chemical processing at air-water interfaces. Combined, these effects can have significant impacts on climate via radiative forcing, but our understanding of organic films at air-water interfaces is incomplete. Here, we examine the impact of the polar headgroup and alkyl tail length on the structure and morphology of organic monolayers at the air-water interfaces. First, we focus on the substituted carboxylic acids, α-keto acids, using Langmuir isotherms and infrared reflection absorption spectroscopy (IR-RAS) to elucidate key structures and phase behaviors of α-keto acids with a range of surface activities. We show that the structure of α-keto acids, both soluble and insoluble, at water surfaces is a compromise between van der Waals interactions of the hydrocarbon tail and hydrogen bonding interactions involving the polar headgroup. Then, we use this new data set regarding α-keto acid films at water surfaces to examine the role of the polar headgroup on organic films using a similar substituted carboxylic acid (α-hydroxystearic acid), an unsubstituted carboxylic acid (stearic acid), and an alcohol (stearyl alcohol). We show that the polar headgroup and its hydrogen bonding interactions can significantly affect the orientation of amphiphiles at air-water interfaces. Here, we provide side-by-side comparisons of Langmuir isotherms and IR-RA spectra for a set of environmentally relevant organic amphiphiles with a range of alkyl tail lengths and polar headgroup structures.
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Affiliation(s)
- Alexandra
M. Deal
- Department
of Chemistry and Cooperative Institute for Research in Environmental
Sciences, University of Colorado Boulder, Boulder, Colorado 80309, United States
| | - Abigail E. Smith
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Krista M. Oyala
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Giovanna H. Campolo
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Burgess E. Rugeley
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Tim A. Mose
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Denver L. Talley
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Christina B. Cooley
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
| | - Rebecca J. Rapf
- Department
of Chemistry, Trinity University, San Antonio, Texas 78212, United States
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2
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Hammami F, Issaoui N. A DFT Study of the Hydrogen Bonded Structures of Pyruvic Acid–Water Complexes. FRONTIERS IN PHYSICS 2022. [DOI: 10.3389/fphy.2022.901736] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The molecular geometries of the possible conformations of pyruvic acid–water complexes (PA-(H2O)n = 1–4) have been fully optimized at DFT/B3LYP/6-311G++ (d, p) levels of calculation. Among several optimized molecular clusters, we present here the most stable molecular arrangements obtained when one, two, three, and four water molecules are hydrogen-bonded to a central pyruvic acid molecule. Appropriate topological and geometrical parameters are considered primary indicators of H-bond strength. Atoms in molecules analysis shows that pyruvic acid can form a ring structure with water, and the molecular structures are stabilized by both strong O–H⋅⋅⋅O and C–H⋅⋅⋅O hydrogen bonds. In large clusters, classical O–H⋅⋅⋅O hydrogen bonds still exist between water molecules, and a cage-like structure is built around some parts of the central molecule of pyruvic acid.
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3
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Kappes K, Frandsen BN, Vaida V. Infrared spectroscopy of 2-oxo-octanoic acid in multiple phases. Phys Chem Chem Phys 2022; 24:6757-6768. [PMID: 35237773 DOI: 10.1039/d1cp05345k] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Alpha-keto acids are environmentally and biologically relevant species whose chemistry has been shown to be influenced by their local environment. Vibrational spectroscopy provides useful ways to probe the potential inter- and intramolecular interactions available to them in several phases. We measure and compare the IR spectra of 2-oxo-octanoic acid (2OOA) in the gas phase, solid phase, and at the air-water interface. With theoretical support, we assign many of the vibrational modes in each of the spectra. In the gas phase, two types of conformers are identified and distinguished, with the intramolecularly H-bonded form being the dominant type, while the second conformer type identified does not have an intramolecular hydrogen bond. The van der Waals interactions between molecules in solid 2OOA manifest C-H and CO vibrations lower in energy than in the gas phase and we propose an intermolecular hydrogen bonding scheme for the solid phase. At the air-water interface the hydrocarbon tails of 2OOA do interact with each other while the carbonyls appear to interact with water in the subphase, but not with neighboring 2OOA as might be expected of a closely packed surfactant film.
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Affiliation(s)
- Keaten Kappes
- Department of Chemistry, University of Colorado-Boulder, UCB 215, Boulder, CO 80309, USA. .,Cooperative Institute for Research in Environmental Sciences, University of Colorado-Boulder, UCB 216, Boulder, CO 80309, USA
| | - Benjamin N Frandsen
- Department of Chemistry, University of Colorado-Boulder, UCB 215, Boulder, CO 80309, USA. .,Cooperative Institute for Research in Environmental Sciences, University of Colorado-Boulder, UCB 216, Boulder, CO 80309, USA
| | - Veronica Vaida
- Department of Chemistry, University of Colorado-Boulder, UCB 215, Boulder, CO 80309, USA. .,Cooperative Institute for Research in Environmental Sciences, University of Colorado-Boulder, UCB 216, Boulder, CO 80309, USA
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4
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Jarraya M, Bellili A, Barreau L, Cubaynes D, Garcia GA, Poisson L, Hochlaf M. Probing the dynamics of the photo-induced decarboxylation of neutral and ionic pyruvic acid. Faraday Discuss 2022; 238:266-294. [DOI: 10.1039/d2fd00023g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dynamics of the electronically excited pyruvic acid (PA) and of its unimolecular decomposition upon single photon ionization are investigated by means of a table top fs laser and VUV...
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5
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Samanta BR, Fernando R, Rösch D, Reisler H, Osborn DL. Primary photodissociation mechanisms of pyruvic acid on S1: observation of methylhydroxycarbene and its chemical reaction in the gas phase. Phys Chem Chem Phys 2021; 23:4107-4119. [DOI: 10.1039/d0cp06424f] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Following S1 ← S0 excitation at 351 nm, pyruvic acid dissociates mainly into methylhydroxycarbene (MHC) and CO2. Some MHC molecules isomerize to more stable acetaldehyde and vinyl alcohol; the remaining MHC is stabilized and reacts bimolecularly.
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Affiliation(s)
- B. R. Samanta
- Department of Chemistry
- University of Southern California
- Los Angeles
- USA
| | - R. Fernando
- Department of Chemistry
- University of Southern California
- Los Angeles
- USA
| | - D. Rösch
- Combustion Research Facility
- Sandia National Laboratories
- Livermore
- USA
| | - H. Reisler
- Department of Chemistry
- University of Southern California
- Los Angeles
- USA
| | - D. L. Osborn
- Combustion Research Facility
- Sandia National Laboratories
- Livermore
- USA
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6
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Blair SL, Reed Harris AE, Frandsen BN, Kjaergaard HG, Pangui E, Cazaunau M, Doussin JF, Vaida V. Conformer-Specific Photolysis of Pyruvic Acid and the Effect of Water. J Phys Chem A 2020; 124:1240-1252. [DOI: 10.1021/acs.jpca.9b10613] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sandra L. Blair
- Department of Chemistry, University of Colorado Boulder, UCB 215, Boulder, Colorado 80309, United States
| | - Allison E. Reed Harris
- Department of Chemistry, University of Colorado Boulder, UCB 215, Boulder, Colorado 80309, United States
| | - Benjamin N. Frandsen
- Department of Chemistry, University of Colorado Boulder, UCB 215, Boulder, Colorado 80309, United States
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark
| | - Henrik G. Kjaergaard
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark
| | - Edouard Pangui
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Institut Pierre Simon Laplace (IPSL), Université Paris-Est Créteil (UPEC) et Université de Paris (UP), 94010 Créteil, France
| | - Mathieu Cazaunau
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Institut Pierre Simon Laplace (IPSL), Université Paris-Est Créteil (UPEC) et Université de Paris (UP), 94010 Créteil, France
| | - Jean-Francois Doussin
- Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), UMR CNRS 7583, Institut Pierre Simon Laplace (IPSL), Université Paris-Est Créteil (UPEC) et Université de Paris (UP), 94010 Créteil, France
| | - Veronica Vaida
- Department of Chemistry, University of Colorado Boulder, UCB 215, Boulder, Colorado 80309, United States
- Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, UCB 216, Boulder, Colorado 80309, United States
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7
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Yamamura R, Suenaga T, Oura M, Tokushima T, Takahashi O. pH dependence of aqueous oxalic acid observed by X-ray absorption and emission spectroscopy. Chem Phys Lett 2020. [DOI: 10.1016/j.cplett.2019.136895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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8
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Wei Y, Cheng J, Yang S, Xiao B, Li Q. Influence of substituents and cooperativity in doubly hydrogen-bonded complexes of 2-pyridone and oxalic acid. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1459918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Yuanxin Wei
- The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai, People's Republic of China
| | - Jianbo Cheng
- The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai, People's Republic of China
| | - Shubin Yang
- The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai, People's Republic of China
| | - Bo Xiao
- The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai, People's Republic of China
| | - Qingzhong Li
- The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai, People's Republic of China
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9
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Keolopile ZG, Ryder MR, Calzada B, Gutowski M, Buytendyk AM, Graham JD, Bowen KH. Electrophilicity of oxalic acid monomer is enhanced in the dimer by intermolecular proton transfer. Phys Chem Chem Phys 2017; 19:29760-29766. [PMID: 29105713 DOI: 10.1039/c7cp00474e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We have analyzed the effect of excess electron attachment on the network of hydrogen bonds in the oxalic acid dimer (OA)2. The most stable anionic structures may be viewed as complexes of a neutral hydrogenated moiety HOA˙ coordinated to an anionic deprotonated moiety (OA-H)-. HOA˙ acts as a double proton donor and (OA-H)- as a double proton acceptor. Thus the excess electron attachment drives intermolecular proton transfer. We have identified several cyclic hydrogen bonded structures of (OA)2-. Their stability has been analyzed in terms of the stability of the involved conformers, the energetic penalty for deformation of these conformers to the geometry of the dimer, and the two-body interaction energy between the deformed HOA˙ and (OA-H)-. There are at least seven isomers of (OA)2- with stabilization energies in the range of 1.26-1.39 eV. These energies are dominated by attractive two-body interaction energies. The anions are vertically bound electronically by 3.0-3.4 eV and adiabatically bound by at least 1.6 eV. The computational predictions are consistent with the anion photoelectron spectrum of (OA)2-. The spectrum consists of a broad feature, with an onset of 2.5 eV and spanning to 4.3 eV. The electron vertical detachment energy (VDE) is assigned to be 3.3 eV.
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Affiliation(s)
- Zibo G Keolopile
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, Scotland EH14 4AS, UK.
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10
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Schnitzler EG, Seifert NA, Ghosh S, Thomas J, Xu Y, Jäger W. Hydration of the simplest α-keto acid: a rotational spectroscopic and ab initio study of the pyruvic acid–water complex. Phys Chem Chem Phys 2017; 19:4440-4446. [DOI: 10.1039/c6cp08741h] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Non-covalent interactions analysis of hydrogen bonding in the pyruvic acid water complex.
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Affiliation(s)
- Elijah G. Schnitzler
- Department of Chemistry
- University of Alberta
- 11227 Saskatchewan Drive
- Edmonton
- Canada
| | - Nathan A. Seifert
- Department of Chemistry
- University of Alberta
- 11227 Saskatchewan Drive
- Edmonton
- Canada
| | - Supriya Ghosh
- Department of Chemistry
- University of Alberta
- 11227 Saskatchewan Drive
- Edmonton
- Canada
| | - Javix Thomas
- Department of Chemistry
- University of Alberta
- 11227 Saskatchewan Drive
- Edmonton
- Canada
| | - Yunjie Xu
- Department of Chemistry
- University of Alberta
- 11227 Saskatchewan Drive
- Edmonton
- Canada
| | - Wolfgang Jäger
- Department of Chemistry
- University of Alberta
- 11227 Saskatchewan Drive
- Edmonton
- Canada
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11
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Chang XP, Fang Q, Cui G. Mechanistic photodecarboxylation of pyruvic acid: Excited-state proton transfer and three-state intersection. J Chem Phys 2014; 141:154311. [DOI: 10.1063/1.4898085] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Xue-Ping Chang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Qiu Fang
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Ganglong Cui
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
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12
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Buonaugurio A, Graham J, Buytendyk A, Bowen KH, Ryder MR, Keolopile ZG, Haranczyk M, Gutowski M. Communication: Remarkable electrophilicity of the oxalic acid monomer: An anion photoelectron spectroscopy and theoretical study. J Chem Phys 2014; 140:221103. [DOI: 10.1063/1.4882655] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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13
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Duan S, Ji YF, Fang PP, Chen YX, Xu X, Luo Y, Tian ZQ. Density functional theory study on the adsorption and decomposition of the formic acid catalyzed by highly active mushroom-like Au@Pd@Pt tri-metallic nanoparticles. Phys Chem Chem Phys 2013; 15:4625-33. [DOI: 10.1039/c3cp44053b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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14
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Raczyńska ED, Hallmann M, Duczmal K. Quantum-chemical studies of amide–iminol tautomerism for inhibitor of lactate dehydrogenase: Oxamic acid. COMPUT THEOR CHEM 2011. [DOI: 10.1016/j.comptc.2011.01.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Canepa P, Chiatti F, Corno M, Sakhno Y, Martra G, Ugliengo P. Affinity of hydroxyapatite (001) and (010) surfaces to formic and alendronic acids: a quantum-mechanical and infrared study. Phys Chem Chem Phys 2010; 13:1099-111. [PMID: 21076734 DOI: 10.1039/c0cp01143f] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The affinity of the (001) and of the water reacted (010)WR hydroxyapatite surfaces towards formic and alendronic acids is studied with density functional theory (PBE functional) using periodic boundary conditions based on Gaussian basis set. Structures, energetic of the adsorption and vibrational features of the adsorbates are computed in order to understand at the atomic level both the cariogenic processes (for the formic acid) and the features of anti-osteoporosis drugs (for the alendronic acid). For both molecules the interaction energy is very high on an absolute scale, and for all examined cases, it is higher on the (010)WR HA surface than on the (001) one. For the latter, a number of cases by which the acidic proton of the adsorbate is transferred to the HA surface are also characterized. For the formic acid case, experimental infrared spectra are also measured and the position and nature of the C=O stretching bands have been found to be in excellent agreement with the quantum mechanical simulations. For alendronic acid IR experiments are still not available and the present predicted infrared spectra will be useful as a guide to interpret future experimental studies.
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Affiliation(s)
- Pieremanuele Canepa
- Dipartimento di Chimica IFM, NIS Centre of Excellence and INSTM (Materials Science and Technology) National Consortium, UdR Torino, Via P. Giuria 7, Torino, Italy
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16
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Reichert D, Montoya A, Liang X, Bockhorn H, Haynes BS. Conformational and Thermodynamic Properties of Gaseous Levulinic Acid. J Phys Chem A 2010; 114:12323-9. [DOI: 10.1021/jp107560u] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Dirk Reichert
- School of Chemical and Biomolecular Engineering, University of Sydney, 2006 Sydney, NSW, Australia, and Karlsruhe Institute of Technology, Engler-Bunte-Institute, Department of Chemical and Process Engineering, D-76131, Germany
| | - Alejandro Montoya
- School of Chemical and Biomolecular Engineering, University of Sydney, 2006 Sydney, NSW, Australia, and Karlsruhe Institute of Technology, Engler-Bunte-Institute, Department of Chemical and Process Engineering, D-76131, Germany
| | - Xiao Liang
- School of Chemical and Biomolecular Engineering, University of Sydney, 2006 Sydney, NSW, Australia, and Karlsruhe Institute of Technology, Engler-Bunte-Institute, Department of Chemical and Process Engineering, D-76131, Germany
| | - Henning Bockhorn
- School of Chemical and Biomolecular Engineering, University of Sydney, 2006 Sydney, NSW, Australia, and Karlsruhe Institute of Technology, Engler-Bunte-Institute, Department of Chemical and Process Engineering, D-76131, Germany
| | - Brian. S. Haynes
- School of Chemical and Biomolecular Engineering, University of Sydney, 2006 Sydney, NSW, Australia, and Karlsruhe Institute of Technology, Engler-Bunte-Institute, Department of Chemical and Process Engineering, D-76131, Germany
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17
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Blair SA, Thakkar AJ. How many intramolecular hydrogen bonds does the oxalic acid dimer have? Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2010.07.019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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18
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Klimovich PV, Mobley DL. Predicting hydration free energies using all-atom molecular dynamics simulations and multiple starting conformations. J Comput Aided Mol Des 2010; 24:307-16. [PMID: 20372973 DOI: 10.1007/s10822-010-9343-7] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2009] [Accepted: 03/16/2010] [Indexed: 11/30/2022]
Abstract
Molecular dynamics simulations in explicit solvent were applied to predict the hydration free energies for 23 small organic molecules in blind SAMPL2 test. We found good agreement with experimental results, with an RMS error of 2.82 kcal/mol over the whole set and 1.86 kcal/mol over all the molecules except several hydroxyl-rich compounds where we find evidence for a systematic error in the force field. We tested two different solvent models, TIP3P and TIP4P-Ew, and obtained very similar hydration free energies for these two models; the RMS difference was 0.64 kcal/mol. We found that preferred conformation of the carboxylic acids in water differs from that in vacuum. Surprisingly, this conformational change is not adequately sampled on simulation timescales, so we apply an umbrella sampling technique to include free energies associated with the conformational change. Overall, the results of this test reveal that the force field parameters for some groups of molecules (such as hydroxyl-rich compounds) still need to be improved, but for most compounds, accuracy was consistent with that seen in our previous tests.
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Affiliation(s)
- Pavel V Klimovich
- Department of Chemistry, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148, USA
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19
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Calzolari A, Monti S, Ruini A, Catellani A. Hydration of cyanin dyes. J Chem Phys 2010; 132:114304. [DOI: 10.1063/1.3352380] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
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