1
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Naito H, Sumi T, Koga K. How do water-mediated interactions and osmotic second virial coefficients vary with particle size? Faraday Discuss 2024; 249:440-452. [PMID: 37791511 DOI: 10.1039/d3fd00104k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
We examine quantitatively the solute-size dependences of the effective interactions between nonpolar solutes in water and in a simple liquid. The potential w(r) of mean force and the osmotic second virial coefficients B are calculated with high accuracy from molecular dynamics simulations. As the solute diameter increases from methane's to C60's with the solute-solute and solute-solvent attractive interaction parameters fixed to those for the methane-methane and methane-water interactions, the first minimum of w(r) lowers from -1.1 to -4.7 in units of the thermal energy kT. Correspondingly, the magnitude of B (<0) increases proportional to σα with some power close to 6 or 7, which reinforces the solute-size dependence of B found earlier for a smaller range of σ [H. Naito, R. Okamoto, T. Sumi and K. Koga, J. Chem. Phys., 2022, 156, 221104]. We also demonstrate that the strength of the attractive interactions between solute and solvent molecules can qualitatively change the characteristics of the effective pair interaction between solute particles, both in water and in a simple liquid. If the solute-solvent attractive force is set to be weaker (stronger) than a threshold, the effective interaction becomes increasingly attractive (repulsive) with increasing solute size.
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Affiliation(s)
- Hidefumi Naito
- Department of Chemistry, Faculty of Science, Okayama University, Okayama 700-8530, Japan.
- Research Institute for Interdisciplinary Science, Okayama University, Okayama 700-8530, Japan
| | - Tomonari Sumi
- Department of Chemistry, Faculty of Science, Okayama University, Okayama 700-8530, Japan.
- Research Institute for Interdisciplinary Science, Okayama University, Okayama 700-8530, Japan
| | - Kenichiro Koga
- Department of Chemistry, Faculty of Science, Okayama University, Okayama 700-8530, Japan.
- Research Institute for Interdisciplinary Science, Okayama University, Okayama 700-8530, Japan
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2
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Reddy KD, Biswas R. Hydrophobic Hydration: A Theoretical Investigation of Structure and Dynamics. J CHEM SCI 2023. [DOI: 10.1007/s12039-022-02123-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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3
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Kustov AV, Smirnova NL. Thermodynamics of TMU-TMU interaction in water, ethylene glycol and formamide – From pair solvophobic interaction to cluster formation. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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Asthagiri DN, Paulaitis ME, Pratt LR. Thermodynamics of Hydration from the Perspective of the Molecular Quasichemical Theory of Solutions. J Phys Chem B 2021; 125:8294-8304. [PMID: 34313434 DOI: 10.1021/acs.jpcb.1c04182] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The quasichemical organization of the potential distribution theorem, molecular quasichemical theory (QCT), enables practical calculations and also provides a conceptual framework for molecular hydration phenomena. QCT can be viewed from multiple perspectives: (a) as a way to regularize an ill-conditioned statistical thermodynamic problem; (b) as an introduction of and emphasis on the neighborship characteristics of a solute of interest; or (c) as a way to include accurate electronic structure descriptions of near-neighbor interactions in defensible statistical thermodynamics by clearly defining neighborship clusters. The theory has been applied to solutes of a wide range of chemical complexity, ranging from ions that interact with water with both long-ranged and chemically intricate short-ranged interactions, to solutes that interact with water solely through traditional van der Waals interations, and including water itself. The solutes range in variety from monatomic ions to chemically heterogeneous macromolecules. A notable feature of QCT is that, in applying the theory to this range of solutes, the theory itself provides guidance on the necessary approximations and simplifications that can facilitate the calculations. In this Perspective, we develop these ideas and document them with examples that reveal the insights that can be extracted using the QCT formulation.
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Affiliation(s)
- Dilipkumar N Asthagiri
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005, United States
| | - Michael E Paulaitis
- Center for Nanomedicine, Johns Hopkins School of Medicine, Baltimore, Maryland 21231, United States
| | - Lawrence R Pratt
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, United States
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5
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Lu D, Fatehi P. A modeling approach for quantitative assessment of interfacial interaction between two rough particles in colloidal systems. J Colloid Interface Sci 2020; 587:24-38. [PMID: 33360896 DOI: 10.1016/j.jcis.2020.11.121] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 11/29/2020] [Accepted: 11/30/2020] [Indexed: 01/21/2023]
Abstract
HYPOTHESIS AND BACKGROUND The simulation of rough particle surface is important to understand and control the interface behavior of particles in colloidal systems. Literature analysis suggested a lack of information for an accurate model simulating the interfacial interaction between two rough particles. It is hypothesized that the total interfacial energy developed between two rough particles would depend on the surface morphologies of particles, and it could be predicted if a mathematical model to represent the interaction of two rough particles were created accurately. EXPERIMENTS In this study, mathematical models were developed to determine the interfacial energy created between two particles according to the XDLVO theory by considering the rippled particle theory and surface element integral (SEI) method. Three different scenarios of particle interactions were assumed in the simulation. The present study provides deep insights into particle interactions via considering aspect ratio, size, and surface roughness of two particles in colloidal systems. FINDINGS The assessment of the interfacial interaction revealed that an increase in the aspect ratio, surface roughness, and relative surface roughness of particles would weaken the total interaction energy generated between particles and promote particle aggregation. Increased interaction energy was predicted for the interaction of particles by increasing the particle size. The asperity ratio was more effective than the asperity number in controlling the interfacial energy between two particles. The results of this study could be used for foreseeing the interaction of rough particles, which has a significant application in particle coagulation or dispersion in colloidal systems.
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Affiliation(s)
- Duowei Lu
- Green Processes Research Centre and Chemical Engineering Department, Lakehead University, 955 Oliver Road, Thunder Bay, ON P7B5E1, Canada
| | - Pedram Fatehi
- Green Processes Research Centre and Chemical Engineering Department, Lakehead University, 955 Oliver Road, Thunder Bay, ON P7B5E1, Canada.
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6
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Ivanov EV, Kustov AV, Batov DV, Smirnova NL, Pechnikova NL. Thermodynamics of tetramethylurea solutions in ethylene glycol: The evidence of pairwise solvophobic interaction. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113994] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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7
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Abstract
Coulomb interactions play a major role in determining the thermodynamics, structure, and dynamics of condensed-phase systems, but often present significant challenges. Computer simulations usually use periodic boundary conditions to minimize corrections from finite cell boundaries but the long range of the Coulomb interactions generates significant contributions from distant periodic images of the simulation cell, usually calculated by Ewald sum techniques. This can add significant overhead to computer simulations and hampers the development of intuitive local pictures and simple analytic theory. In this paper, we present a general framework based on local molecular field theory to accurately determine the contributions from long-ranged Coulomb interactions to the potential of mean force between ionic or apolar hydrophobic solutes in dilute aqueous solutions described by standard classical point charge water models. The simplest approximation leads to a short solvent (SS) model, with truncated solvent-solvent and solute-solvent Coulomb interactions and long-ranged but screened Coulomb interactions only between charged solutes. The SS model accurately describes the interplay between strong short-ranged solute core interactions, local hydrogen-bond configurations, and long-ranged dielectric screening of distant charges, competing effects that are difficult to capture in standard implicit solvent models.
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8
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Barnett JW, Ashbaugh HS. Evaluation of second osmotic virial coefficients from molecular simulation following scaled-particle theory. MOLECULAR SIMULATION 2019. [DOI: 10.1080/08927022.2019.1639698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- J. Wesley Barnett
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA, USA
| | - Henry S. Ashbaugh
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA, USA
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9
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Abstract
Hydration-shell vibrational spectroscopy provides an experimental window into solute-induced water structure changes that mediate aqueous folding, binding, and self-assembly. Decomposition of measured Raman and infrared (IR) spectra of aqueous solutions using multivariate curve resolution (MCR) and related methods may be used to obtain solute-correlated spectra revealing solute-induced perturbations of water structure, such as changes in water hydrogen-bond strength, tetrahedral order, and the presence of dangling (non-hydrogen-bonded) OH groups. More generally, vibrational-MCR may be applied to both aqueous and nonaqueous solutions, including multicomponent mixtures, to quantify solvent-mediated interactions between oily, polar, and ionic solutes, in both dilute and crowded fluids. Combining vibrational-MCR with emerging theoretical modeling strategies promises synergetic advances in the predictive understanding of multiscale self-assembly processes of both biological and technological interest.
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Affiliation(s)
- Dor Ben-Amotz
- Department of Chemistry , Purdue University , West Lafayette , Indiana 47907 , United States
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10
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Ribeiro GH, Colina-Vegas L, Clavijo JC, Ellena J, Cominetti MR, Batista AA. Ru(II)/N-N/PPh3 complexes as potential anticancer agents against MDA-MB-231 cancer cells (N-N = diimine or diamine). J Inorg Biochem 2019; 193:70-83. [DOI: 10.1016/j.jinorgbio.2019.01.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 01/10/2019] [Accepted: 01/12/2019] [Indexed: 01/27/2023]
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11
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Chialvo AA, Crisalle OD. On the behavior of the osmotic second virial coefficients of gases in aqueous solutions: Rigorous results, accurate approximations, and experimental evidence. J Chem Phys 2019; 150:124503. [DOI: 10.1063/1.5047525] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
| | - Oscar D. Crisalle
- Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, USA
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12
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Islam N, Flint M, Rick SW. Water hydrogen degrees of freedom and the hydrophobic effect. J Chem Phys 2019; 150:014502. [DOI: 10.1063/1.5053239] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Naeyma Islam
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148, USA
| | - Mahalia Flint
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148, USA
| | - Steven W. Rick
- Department of Chemistry, University of New Orleans, New Orleans, Louisiana 70148, USA
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13
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Wu X, Lu W, Streacker LM, Ashbaugh HS, Ben‐Amotz D. Methane Hydration‐Shell Structure and Fragility. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201809372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Xiangen Wu
- College of Marine Science and Technology China University of Geosciences Wuhan 430074 China
| | - Wanjun Lu
- State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China
| | | | - Henry S. Ashbaugh
- Department of Chemical and Biomolecular Engineering Tulane University New Orleans Louisiana 70118 USA
| | - Dor Ben‐Amotz
- Purdue University Department of Chemistry West Lafayette IN 47907 USA
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14
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Wu X, Lu W, Streacker LM, Ashbaugh HS, Ben-Amotz D. Methane Hydration-Shell Structure and Fragility. Angew Chem Int Ed Engl 2018; 57:15133-15137. [PMID: 30368997 DOI: 10.1002/anie.201809372] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Indexed: 11/12/2022]
Abstract
The influence of oily molecules on the structure of liquid water is a question of importance to biology and geology and many other fields. Previous experimental, theoretical, and simulation studies of methane in liquid water have reached widely conflicting conclusions regarding the structure of hydrophobic hydration-shells. Herein we address this question by performing Raman hydration-shell vibrational spectroscopic measurements of methane in liquid water from -10 °C to 300 °C (at 30 MPa, along a path that parallels the liquid-vapor coexistence curve). We show that, near ambient temperatures, methane's hydration-shell is slightly more tetrahedral than pure water. Moreover, the hydration-shell undergoes a crossover to a more disordered structure above ca. 85 °C. Comparisons with the crossover temperature of aqueous methanol (and other alcohols) reveal the stabilizing influence of an alcohol OH head-group on hydrophobic hydration-shell fragility.
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Affiliation(s)
- Xiangen Wu
- College of Marine Science and Technology, China University of Geosciences, Wuhan, 430074, China
| | - Wanjun Lu
- State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan, 430074, China
| | - Louis M Streacker
- Purdue University, Department of Chemistry, West Lafayette, IN, 47907, USA
| | - Henry S Ashbaugh
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana, 70118, USA
| | - Dor Ben-Amotz
- Purdue University, Department of Chemistry, West Lafayette, IN, 47907, USA
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15
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Gao A, Tan L, Chaudhari MI, Asthagiri D, Pratt LR, Rempe SB, Weeks JD. Role of Solute Attractive Forces in the Atomic-Scale Theory of Hydrophobic Effects. J Phys Chem B 2018; 122:6272-6276. [DOI: 10.1021/acs.jpcb.8b01711] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Ang Gao
- Institute for Physical Science and Technology, and Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Liang Tan
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, United States
| | - Mangesh I. Chaudhari
- Center for Biological and Engineering Sciences, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - D. Asthagiri
- Chemical and Biomolecular Engineering Rice University, Houston, Texas 77005, United States
| | - Lawrence R. Pratt
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, Louisiana 70118, United States
| | - Susan B. Rempe
- Center for Biological and Engineering Sciences, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - John D. Weeks
- Institute for Physical Science and Technology, and Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
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16
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Asthagiri D, Karandur D, Tomar DS, Pettitt BM. Intramolecular Interactions Overcome Hydration to Drive the Collapse Transition of Gly 15. J Phys Chem B 2017; 121:8078-8084. [PMID: 28774177 DOI: 10.1021/acs.jpcb.7b05469] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Simulations and experiments show oligo-glycines, polypeptides lacking any side chains, can collapse in water. We assess the hydration thermodynamics of this collapse by calculating the hydration free energy at each of the end points of the reaction coordinate, here taken as the end-to-end distance (r) in the chain. To examine the role of the various conformations for a given r, we study the conditional distribution, P(Rg|r), of the radius of gyration for a given value of r. The free energy change versus Rg, -kBT ln P(Rg|r), is found to vary more gently compared to the corresponding variation in the excess hydration free energy. Using this observation within a multistate generalization of the potential distribution theorem, we calculate a tight upper bound for the hydration free energy of the peptide for a given r. On this basis, we find that peptide hydration greatly favors the expanded state of the chain, despite primitive hydrophobic effects favoring chain collapse. The net free energy of collapse is seen to be a delicate balance between opposing intrapeptide and hydration effects, with intrapeptide contributions favoring collapse.
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Affiliation(s)
- D Asthagiri
- Department of Chemical and Biomolecular Engineering, Rice University , Houston, Texas, United States.,Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch , Galveston, Texas, United States
| | - Deepti Karandur
- Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine , Houston, Texas, United States
| | - Dheeraj S Tomar
- Chemical and Biomolecular Engineering, Johns Hopkins University , Baltimore, Maryland, United States
| | - B Montgomery Pettitt
- Sealy Center for Structural Biology and Molecular Biophysics, University of Texas Medical Branch , Galveston, Texas, United States.,Structural and Computational Biology and Molecular Biophysics, Baylor College of Medicine , Houston, Texas, United States
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17
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Asthagiri D, Valiya Parambathu A, Ballal D, Chapman WG. Electrostatic and induction effects in the solubility of water in alkanes. J Chem Phys 2017; 147:074506. [DOI: 10.1063/1.4997916] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Affiliation(s)
- D. Asthagiri
- Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005-1827, USA
| | | | - Deepti Ballal
- Materials Science and Engineering, Ames Laboratory, Ames, Iowa 50011, USA
| | - Walter G. Chapman
- Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005-1827, USA
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18
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Chaudhari MI, Pratt LR, Rempe SB. Utility of chemical computations in predicting solution free energies of metal ions. MOLECULAR SIMULATION 2017. [DOI: 10.1080/08927022.2017.1342127] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Mangesh I. Chaudhari
- Center for Biological and Engineering Sciences, Sandia National Laboratories, Albuquerque, NM, USA
| | - Lawrence R. Pratt
- Department of Chemical and Biomolecular Engineering, Tulane University, New Orleans, LA, USA
| | - Susan B. Rempe
- Center for Biological and Engineering Sciences, Sandia National Laboratories, Albuquerque, NM, USA
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19
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He Z, Linga P, Jiang J. What are the key factors governing the nucleation of CO 2 hydrate? Phys Chem Chem Phys 2017; 19:15657-15661. [PMID: 28530729 DOI: 10.1039/c7cp01350g] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Microsecond molecular dynamics simulations were performed to provide molecular insights into the nucleation of CO2 hydrate. The adsorption of sufficient CO2 molecules around CO2 hydration shells is revealed to be crucial to effectively stabilize the hydrogen bonds formed therein, catalyzing the hydration shells into hydrate cages and inducing the nucleation. Moreover, a high aqueous CO2 concentration is found to be another key factor governing the nucleation of CO2 hydrate, and only above a critical concentration can the nucleation of CO2 hydrate occur. The 4151062 cages, with size similar to the CO2 hydration shell and an elliptical space closely matching a linear CO2 molecule, play a dominant role in initiating the nucleation and remain the most abundant. The incipient CO2 hydrate is rather amorphous due to the abundance of metastable cages (mostly 4151062).
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Affiliation(s)
- Zhongjin He
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 117576, Singapore, Singapore.
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20
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Cerdeiriña CA, Widom B. Osmotic Second Virial Coefficients of Aqueous Solutions from Two-Component Equations of State. J Phys Chem B 2016; 120:13144-13151. [DOI: 10.1021/acs.jpcb.6b09912] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Claudio A. Cerdeiriña
- Departamento
de Física Aplicada, Universidad de Vigo, Campus del Agua, Ourense 32004, Spain
- Department
of Chemistry, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, United States
| | - B. Widom
- Department
of Chemistry, Baker Laboratory, Cornell University, Ithaca, New York 14853-1301, United States
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21
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Raineri FO. Hydration thermodynamics beyond the linear response approximation. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:414014. [PMID: 27546004 DOI: 10.1088/0953-8984/28/41/414014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The solvation energetics associated with the transformation of a solute molecule at infinite dilution in water from an initial state A to a final state B is reconsidered. The two solute states have different potentials energies of interaction, [Formula: see text] and [Formula: see text], with the solvent environment. Throughout the A [Formula: see text] B transformation of the solute, the solvation system is described by a Hamiltonian [Formula: see text] that changes linearly with the coupling parameter ξ. By focusing on the characterization of the probability density [Formula: see text] that the dimensionless perturbational solute-solvent interaction energy [Formula: see text] has numerical value y when the coupling parameter is ξ, we derive a hierarchy of differential equation relations between the ξ-dependent cumulant functions of various orders in the expansion of the appropriate cumulant generating function. On the basis of this theoretical framework we then introduce an inherently nonlinear solvation model for which we are able to find analytical results for both [Formula: see text] and for the solvation thermodynamic functions. The solvation model is based on the premise that there is an upper or a lower bound (depending on the nature of the interactions considered) to the amplitude of the fluctuations of Y in the solution system at equilibrium. The results reveal essential differences in behavior for the model when compared with the linear response approximation to solvation, particularly with regards to the probability density [Formula: see text]. The analytical expressions for the solvation properties show, however, that the linear response behavior is recovered from the new model when the room for the thermal fluctuations in Y is not restricted by the existence of a nearby bound. We compare the predictions of the model with the results from molecular dynamics computer simulations for aqueous solvation, in which either (1) the solute-solvent electrostatic interactions, or (2) the shorter-range attractive interactions are switched-on in the A [Formula: see text] B process.
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Affiliation(s)
- Fernando O Raineri
- Department of Chemistry, Stony Brook University, Stony Brook, NY 11794, USA
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22
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Pratt LR, Chaudhari MI, Rempe SB. Statistical Analyses of Hydrophobic Interactions: A Mini-Review. J Phys Chem B 2016; 120:6455-60. [PMID: 27258151 DOI: 10.1021/acs.jpcb.6b04082] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This review focuses on the striking recent progress in solving for hydrophobic interactions between small inert molecules. We discuss several new understandings. First, the inverse temperature phenomenology of hydrophobic interactions, i.e., strengthening of hydrophobic bonds with increasing temperature, is decisively exhibited by hydrophobic interactions between atomic-scale hard sphere solutes in water. Second, inclusion of attractive interactions associated with atomic-size hydrophobic reference cases leads to substantial, nontrivial corrections to reference results for purely repulsive solutes. Hydrophobic bonds are weakened by adding solute dispersion forces to treatment of reference cases. The classic statistical mechanical theory for those corrections is not accurate in this application, but molecular quasi-chemical theory shows promise. Finally, because of the masking roles of excluded volume and attractive interactions, comparisons that do not discriminate the different possibilities face an interpretive danger.
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Affiliation(s)
- Lawrence R Pratt
- Department of Chemical and Biomolecular Engineering, Tulane University , New Orleans, Louisiana 70118, United States
| | - Mangesh I Chaudhari
- Center for Biological and Engineering Sciences, Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
| | - Susan B Rempe
- Center for Biological and Engineering Sciences, Sandia National Laboratories , Albuquerque, New Mexico 87185, United States
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