Ion Distribution and Hydration Structure in the Stern Layer on

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Ion Distribution and Hydration Structure in the Stern Layer on Muscovite Surface Kazuya Kobayashi, Yunfeng Liang, Sumihiko Murata, Toshifumi Matsuoka, Satoru Takahashi, Naoya Nishi, and Tetsuo Sakka Langmuir, Just Accepted Manuscript • DOI: 10.1021/acs.langmuir.7b00436 • Publication Date (Web): 29 Mar 2017 Downloaded from http://pubs.acs.org on March 31, 2017

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Ion Distribution and Hydration Structure in the Stern Layer on Muscovite Surface Kazuya Kobayashi,1,2,* Yunfeng Liang,2,3,* Sumihiko Murata,2 Toshifumi Matsuoka,2,4 Satoru Takahashi,5 Naoya Nishi,1 and Tetsuo Sakka1 1

Department of Energy and Hydrocarbon Chemistry, Kyoto University, Kyoto 615-8510, Japan

2

Environment and Resource System Engineering, Kyoto University, Kyoto 615-8540, Japan

3

Center for Engineering, Research into Artifacts (RACE), the University of Tokyo, Chiba 277-

8568, Japan 4

Fukada Geological Institute, Tokyo 113-0021, Japan

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Japan Oil, Gas and Metals National Corporation (JOGMEC), Chiba 261-0025, Japan

*

Corresponding author: Kazuya Kobayashi

Postal address: Kyoto University Room C1-1-108 Kyotodaigaku-Katsura, Nishikyoku Kyoto 615-8540, Japan Tel:

+81-75-383-3206

Email:

[email protected]

*

Corresponding author: Yunfeng Liang

Email:

[email protected]

ACS Paragon Plus Environment

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Abstract: Based on molecular dynamics simulations of eight ions (Na+, K+, Rb+, Cs+, Mg2+, Ca2+, Sr2+, Ba2+) on muscovite mica surfaces, we demonstrate that experimental data on the muscovite mica surface can be rationalized through a unified picture of adsorption structures including the hydration structure, cation heights from the muscovite surface, and state stability. These simulations enable us to categorize the inner-sphere surface complex into two different species: an inner-sphere surface complex in a ditrigonal cavity (IS1) and that on top of Al (IS2). By considering the presence of the two inner-sphere surface complexes, the experimental finding that the heights of adsorbed cations from the muscovite surface are proportional to the ionic radius for K+ and Cs+ but inversely proportional to the ionic radius for Ca2+ and Ba2+ was explained. We find that Na+, Ca2+, Sr2+, and Ba2+ can form both IS1 and IS2; K+, Rb+, and Cs+ can form only IS1; and Mg2+ can form only IS2. It is suggested that the formation of IS1 and IS2 is governed by the charge density of the ions. Among the eight ions, we also find that the hydration structure for the outer-sphere surface complexes of divalent cations differs from that of the monovalent cations by one adsorbed water molecule (i.e., a water molecule located in a ditrigonal cavity).


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Introduction The interaction between charged surfaces mediated by aqueous solutions is fundamental to understanding various natural and industrial processes. For example, this interaction governs the transport of elements,1-6 stability of colloidal dispersions,7-11 and wettability at solid surfaces.12-16 The difference in the interaction depending on ionic species in aqueous solutions leads to ionspecific results for these processes. Therefore, attaining a better understanding of the ion-specific interaction at a charged surface is critical.17-18 This interaction must be understood at the molecular rather than the mean-field level because mean-field theories such as the classical Gouy–Chapman theory and DLVO theory have limitations in describing certain phenomena concerning the Stern layer (e.g., charge reversal,4,19,20 adsorbed ion-ion correlations,21 and hydration forces8-11). Muscovite mica is a representative clay mineral that provides an atomically smooth cleavage (001) surface. Substitution of Si4+ with Al3+ yields a negative charge at the muscovite surface, which is initially compensated by adsorbed K+. Many experimental studies, for example, X-ray reflectivity,2-6,22-29 atomic force microscopy (AFM),11,21,30-34 and surface force apparatus studies,7-10,35 have been performed on muscovite surfaces in aqueous solutions. X-ray reflectivity studies have demonstrated that cations at the muscovite surface can coexist both as inner-sphere surface complexes (IS) and outer-sphere surface complexes (OS) with a cation-dependent distribution.4,5,22-25 The two adsorbed species are identified by the height of cations from the surface and a deduced hydrated state of the ion on surfaces. No water molecule is interposed between the surface and cation for IS, whereas at least one water molecule is interposed for OS.1 Although the distribution normal to the surfaces obtained by X-ray reflectivity is useful to identify the adsorbed species (IS or OS), the lateral positions of cations at the muscovite surface


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is also important. Figure 1a presents an atomic-scale image of the muscovite surface, where substituted Al is represented by blue spheres. AFM experiments have indicated the presence of two possible sites for cations:21,34 the cavity site (i.e., the location of pink sphere in Figure 1a) and on the Al site (on top of the blue sphere in Figure 1a). Ricci et al. detected K+ and Rb+ in the cavity site.21 Li+, Na+, Mg2+, and Ca2+ have been detected on the Al site by Loh et al.34 Although X-ray reflectivity and AFM have provided substantial information normal and tangential to the muscovite surface, respectively, a unified picture of the cation distribution and hydration structures in the Stern layer of the muscovite surface has not yet been attained. For example, an X-ray reflectivity study demonstrated that the height of adsorbed monovalent cations (K+ and Cs+) at the muscovite surface is proportional to the ionic radius, whereas the height of adsorbed divalent cations (Ca2+ and Ba2+) at the muscovite surface is inversely proportional to the ionic radius.26 It is critical to understand the underlying mechanism for this observation and determine how to unify the AFM and X-ray reflectivity results, that is, the hydration states suggested in the X-ray reflectivity experiments must be determined for the two possible adsorption sites reported in the AFM experiments. Molecular simulations are useful to visualize the atomic structure near surfaces. Indeed, the atomic structure at the muscovite surface and its effects on experimental observations have been intensively reported.6,28,29,36-41 Sakuma et al. demonstrated that the hydration structures at the muscovite surface covered by different monovalent cations obtained by molecular dynamics (MD) simulation and X-ray reflectivity are consistent with each other.6 However, the structures of ions in the Stern layer at the muscovite surface have seldom been discussed, presumably because a long computing time and large surface area are needed to equilibrate the ionic structures for molecular simulations. Rare-event simulations38-41 have been implemented to


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overcome the shortcomings of MD simulations; however, these studies are limited to discussions of individual ions. Here, we utilize MD simulations and calculations of the potential of mean force (PMF) to study the Stern layer structures of monovalent cations (Na+, K+, Rb+, Cs+) and divalent cations (Mg2+, Ca2+, Sr2+, Ba2+) at muscovite/solution interfaces. The key finding of our study is the provision of a unified picture of the cation adsorption structure by categorizing the inner-sphere surface complex into two different species.

Figure 1. Simulation system, where the yellow, red, blue, pink, and green spheres represent Si, O, Al, monovalent cations, and divalent cations, respectively: a) initial lateral position of monovalent cations, b) initial lateral position of divalent cations, and c) interfacial system between muscovite and water.

Computational Methods Images of the simulation systems are presented in Figure 1. The atomic coordinates of muscovite were determined by Richardson using X-ray diffraction.42 The chemical formula of muscovite is K+[Al2(Si3Al)O10(OH)2]-. Substitution of Si4+ with Al3+ was regularly performed (Figures 1a and


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1b) and octahedral substitution was not performed according to the chemical formula. Cations have been reported to be distributed in an ordered manner at the muscovite surface.21 We applied the rule that cations are initially located at Si4Al2 cavity sites in our model, and the number of cations required to obtain a neutral surface charge was determined (Figures 1a and 1b). The substitution could be implemented randomly rather than regularly. The random substitution would give other stable sites for cations (e.g., Si3Al3) and more heterogeneous charge distribution. However, for comparison among eight cations, the well-ordered system is beneficial. Eight interfacial systems (Figure 1c) were constructed by combining a cation-covered surface, as observed in Figure 1a or 1b with pure water. We used periodic boundary condition for the simulation system. The muscovite slab was 3.1 × 2.7 × 2.0 nm. The pure water phase contained 1,400 water molecules. At ambient conditions, this resulted in ~5 nm aqueous phase normal to the interface, which gives a separation distance long enough for PMFs to be constant. Umbrella sampling simulations43,44 were implemented with this system to obtain PMFs of the cations at the muscovite surface. First, we selected a representative cation from the adsorbed cations at the muscovite surface and pulled it to the aqueous bulk by imposing a harmonic potential (kh = 4000 kJ/mol nm2) on the cation and moving the potential center to the aqueous bulk at a rate of 0.001 nm/ps. The configurations obtained by this simulation were used for initial configurations in the following umbrella sampling simulations. The distance, D, between the representative cation and muscovite surface oxygen plane was selected as a reaction coordinate. Then, 55 window calculations (3.1 ns for equilibration + 3.0 ns for production) with a harmonic potential (kh = 4000 kJ/mol nm2) were implemented from D = 0.115 nm with a 0.025-nm interval as a standard case. We assigned initial velocities of atoms with random number after energy minimization of the initial configurations when we started a calculation at each window. Therefore, the


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calculations are independent for each window. We determined that ill-sampling could occur with this setting for some cations because of bumpy PMFs, as described later. We refined the windows with a steeper harmonic potential in the ill-sampling region. Since overlapping of umbrella histograms of a reaction coordinate from each window is more critical than simulation time,45,46 we have confirmed that at least 3 or 4 histograms cover a certain value of the reaction coordinate (D) of interest (Figure S1). The parameters of the windows used to generate PMFs in this study are summarized in Tables S1 and S2 in the supporting information. The errors in the original data were estimated by standard deviation of bootstrap samples.47 The harmonic potentials used in the calculation only worked normal to the muscovite surface. Thus, the representative cation can freely move tangentially to the muscovite surface. In contrast to the representative cations, the other cations were constrained at their initial positions by threedimensional harmonic potentials (kh = 4000 kJ/mol nm2). Although the constraints might affect the PMFs, they make our system well-defined during the entire simulation procedure to allow a fair comparison among the eight cations. Without the constraints, a few non-representative cations are desorbed from the muscovite surface (e.g., Na+). This small fraction of the occasionally desorbed cations would require a significantly longer simulation time and deteriorate the fair comparison among the cations. We confirmed that the non-representative cations with the constraints remained at the same position calculated by the MD simulations without constraints (Figure S2). Therefore, we benefited from the application of the constraints because the artifacts from the constraints on the interfacial structure near the representative cation were considered sufficiently small in our calculations. To generate the PMF, the weighted histogram analysis method was implemented.48,49


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We used GROMACS 4.5.650 for the MD simulations. The force fields for the muscovite, monovalent cations, divalent cations, and water were CLAYFF,51 the Joung and Cheatham model,52 the Åqvist model,53 and SPC/E,54, respectively. The models of ions accurately represent the hydration Gibbs energy52,53 and solubility of salts.55 The Lennard–Jones (LJ) parameters for unlike atoms were determined using the Lorentz–Berthelot rule. The cut-off radius was 1.0 nm for both the LJ and Coulombic potential. The long-range interaction for the Coulombic potential was treated using the smooth-particle Ewald summation method.56 All the calculations were implemented with the NpT ensemble, where temperature and pressure were controlled to be ambient conditions (298 K and 1 bar) by the Nose–Hoover thermostat (τT = 2.0 ps)57,58 and Parrinello–Rahman barostat (τp = 5.0 ps),59 respectively. Anisotropic scaling without shear deformation was set for the barostat. Visual Molecular Dynamics (VMD) software was used for visualizations of snapshots from the simulations.60 Results and Discussion Adsorption states of cations at muscovite surface Figure 2 represents the PMFs as a function of the distance (D) between the representative cation and muscovite surface for the monovalent cations (a) and divalent cations (b). Figure 2 clearly reveals that the PMFs have a few minimum points at the muscovite surface and that the minimum points depend on the type of cations. This finding demonstrates that different cations have different adsorption states and affinities at the muscovite surface.


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Figure 2. Potential of mean force (PMF) as a function of distance (D) between the representative cation and muscovite surface: a) monovalent cations and b) divalent cations. The inset figure in a) presents a schematic image of the PMF of Na+ and the definition of the adsorption states.

Starting from differences among the monovalent cations (Figure 2a), Na+ has distinctive features; that is, Na+ has three minimum points (two points near D = 0.2 nm and one point near D = 0.5 nm in Figure 2a), whereas the other monovalent cations have two points (near D = 0.2 nm and D = 0.5 nm in Figure 2a). This finding demonstrates that Na+ can form three distinct


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adsorption states, whereas the others can form two distinct adsorption states. We calculated the radial distribution function (RDF) and coordination number for the adsorption states (Figure S3). The coordination numbers of the water molecule in the states near the first and second nearest minimum points in the PMF (Figure 2a) are approximately 2 and 4, respectively (the red and green broken line in the left panel in Figure S3 (a)). These values are less than the coordination number of water for Na+ in bulk aqueous solution (4.9 from a recent neutron diffraction study61 and 5 to 7 from molecular simulations62-72). In contrast, the coordination number of the water molecule in the state near the third nearest minimum point (nw = 5.9) is similar to that in bulk aqueous solution. Here, we determined that the third nearest minimum point corresponds to the outer-sphere surface complex and that the other minimum points correspond to inner-sphere surface complexes. When we examined the nearest neighbor numbers of Al around Na+ in the three states (the right panel in Figure S3 (a)), two Al were around Na+ in the state near the first nearest minimum point (red broken line), one Al was around Na+ in the state near the second nearest minimum point (green broken line), and no Al was around Na+ in the state near the third nearest minimum point (blue broken line). The two Al around Na+ indicates that Na+ is adsorbed in a Si4Al2 ditrigonal cavity site, and one Al around Na+ indicates that Na+ is adsorbed on top of Al. In summary, we determined that there are three distinct adsorption states for Na+ at the muscovite surface: an inner-sphere surface complex in a ditrigonal cavity site (IS1), an innersphere surface complex at an Al site (IS2), and an outer-sphere surface complex (OS). In addition, the order of the water coordination number is IS1 < IS2 < OS. The same analysis for the other monovalent cations (Figure S3 (b) to (d)) revealed that the first and second nearest minimum points observed in the PMFs in Figure 2a correspond to an inner-sphere surface complex with two Al (IS1) and an outer-sphere surface complex (OS), respectively. In fact, the


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result that Na+ forms more adsorption states at the muscovite surface than the other monovalent cations is consistent with the snapshot from the MD simulation presented by Ricci et al.21 The adsorption Gibbs energies obtained from the PMFs are summarized in Table 1. When we compare ∆GIS1 for the monovalent cations, we obtain an order of affinity of Na+ IS2 for Ca2+ and Ba2+, respectively) estimated by the Boltzmann factor. In summary, a three-dimensional unified picture of the cation structure in the Stern layer of the muscovite surface has been refined by the idea of IS1 and IS2 obtained from our simulations. Conclusion In this paper, we implemented MD simulations and PMF calculations to obtain a unified picture of the Stern layer of the muscovite cleavage (001) surface (hydration structure, cation heights from the muscovite surface, and state stability). The results obtained from eight different cations (Na+, K+, Rb+, Cs+, Mg2+, Ca2+, Sr2+, Ba2+) indicate the presence of three different possible adsorption states: IS1, IS2, and OS. In addition, it is implied that the distribution and formation of each state are well correlated to the charge density of the cations. For the outersphere surface complexes, we determined that the hydration structure for the outer-sphere surface complexes was different for monovalent and divalent cations. This difference results in a height difference of the cations in the outer-sphere surface complexes. One of the key findings from this study, the idea of two different inner-sphere surface complexes, provides an


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explanation for the heights of the cations near the muscovite surface being proportional to the ionic radius for K+ and Cs+ but inversely proportional to the ionic radius for Ca2+ and Ba2+. Our simulations support previous experimental results2,3,5,21,23-26,29,32,34 and provide useful predictions. Acknowledgements This research was supported by the Japanese Society for the Promotion of Science (JSPS) through a Grant-in-Aid for JSPS Fellows (no. 16J00156), Grant-in-Aid for Scientific Research A (no. 24246148), and Grant-in-Aid for Scientific Research C (no. 16K06925). We further acknowledge funding from the Japan Science and Technology Agency (JST)/Japan International Cooperation Agency (JICA) – Science and Technology Research Partnership for Sustainable Development (SATREPS), and Japan Petroleum Exploration Co., Ltd. (JAPEX). We also wish to thank Ken-ichi Amano for valuable discussions.

Supporting Information Supporting Information Available: Table of calculation settings for umbrella sampling, fitted parameters for the regression lines in Figure 5. The local structure around Ca2+ at the muscovite surface (a) with and (b) without constraints. The RDFs and coordination numbers around adsorbed cations. Number density isosurfaces (100/nm3) of water molecule around inner-sphere surface complexes of divalent cations. These materials are available free of charge via the Internet at http://pubs.acs.org. Competing financial interests The authors declare no competing financial interests.


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References (1) Sposito, G.; Skipper, N. T.; Sutton, R.; Park, S.-H.; Soper, A. K.; Greathouse, J. A. Surface Geochemistry of the Clay Minerals. Proc. Natl. Acad. Sci. USA 1999, 96, 3358–3364. (2) Lee, S. S.; Nagy, K. L.; Fenter, P. Distribution of Barium and Fulvic Acid at the Mica– Solution Interface Using in-situ X-ray Reflectivity. Geochim. Cosmochim. Acta 2007, 71, 5763–5781. (3) Lee, S. S.; Park, C.; Fenter, P.; Sturchio, N. C.; Nagy, K. L. Competitive Adsorption of Strontium and Fulvic Acid at the Muscovite –Solution Interface Observed with Resonant Anomalous X-ray Reflectivity. Geochim. Cosmochim. Acta. 2010, 74, 1762–1776. (4) Lee S. S.; Schmidt, M.; Laanait, N.; Sturchio, N. C.; Fenter, P. Investigation of Structure, Adsorption Free Energy and Overcharging Behavior of Trivalent Yttrium Adsorbed at the Muscovite (001) – Water Interface. J. Phys. Chem. C 2013, 117, 23738–23749. (5) Lee, S. S.; Fenter, P.; Nagy, K. L.; Sturchio, N. C. Changes in Adsorption Free Energy and Speciation during Competitive Adsorption between Monovalent Cations at the Muscovite (001) - Water Interface. Geochim. Cosmochim. Acta 2013, 123, 416–426. (6) Sakuma, H.; Kawamura, K. Structure and Dynamics of Water on Li+-, Na+-, K+-, Cs+-, H3O+Exchanged Muscovite Surfaces: A Molecular Dynamics Study. Geochim. Cosmochim. Acta 2011, 75, 63–81. (7) Alcanter, N.; Israelachivili, J.; Boles, J. Forces and Ionic Transport between Mica Surfaces: Implications for Pressure Solution. Geochim. Cosmochim. Acta 2003, 67, 1289–1304. (8) Pashley, R. M. DLVO and Hydration Forces between Mica Surfaces in Li+, Na+, K+, and Cs+ Electrolyte Solutions: A Correlation of Double-Layer and Hydration Forces with Surface Cation Exchange Properties. J. Colloid Interface Sci. 1981, 83, 531–546.


22

Page 23 of 37

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

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(9) Pashley, R. M.; Israelachvili, J. N. DLVO and Hydration Forces between Mica Surfaces in Mg2+, Ca2+, Sr2+, Ba2+ Chloride Solutions. J. Colloid Interface Sci. 1984, 97, 446455. (10)

Pashley, R. M. Hydration Forces between Mica Surfaces in Electrolyte Solutions. Adv.

Colloid Interface Sci. 1982, 16, 57–62. (11)

Higashitani, K.; Ishimura, K. Evaluation of Interaction Forces between Surfaces in

Electrolyte Solutions by Atomic Force Microscope. J. Chem. Eng. Japan 1997, 30, 52–58. (12)

Buckley, J. S. Effective Wettability of Minerals Exposed to Crude Oil. Curr. Opin.

Colloid Interface Sci. 2001, 6, 191–196. (13)

Kumer, K.; Dao, E.; Mohanty, K. K. AFM Study of Mineral Wettability with Reservoir

Oils. J. Colloid Interface Sci. 2005, 289, 206–217. (14)

Aslan, S.; Najafabadi, N. F.; Firoozabadi, A. Non-monotonicity of the Contact Angle

from NaCl and MgCl2 Concentrations in Two Petroleum Fluids on Atomistically Smooth Surfaces. Energy Fuels 2016, 30, 2858–2864. (15)

Mugele, F.; Bera, B.; Cavalli, A.; Siretanu, I.; Maestro, A.; Duits, M.; Cohen-Stuart, M.;

van den Ende, D.; Stocker, E.; Collins, I. Ion Adsorption-Induced Wetting Transition in OilWater-Mineral Systems. Sci. Rep. 2013, 5, 10519. (16)

Standal, S.; Haavik, J.; Blokhus, A. M.; Skauge, A. Effect of Polar Organic Components

on Wettability as Studied by Adsorption and Contact Acgles. J. Petrol. Sci. Eng. 1999, 24, 131–144. (17)

Salis, A.; Ninham, B. W. Models and Mechanisms of Hofmeister Effects in Electrolyte

Solutions and Colloid and Protein Systems Revisited. Chem. Soc. Rev. 2014, 43, 7358–7377. (18)

Schwierz, N.; Horinek, D.; Netz, R. R. Specific Ion Binding to Carboxylic Surface

Groups and the pH Dependence of the Hofmeister Series. Langmuir 2015, 31, 215–225.


23

Langmuir

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(19)

Page 24 of 37

Martin-Molina, A.; Quesada-Pérez, M.; Galisteo-González, F.; Hidalgo-Álvarez, R.

Looking into Overcharging in Model Colloids Through Electrophoresis Asymmetric Electrolytes. J. Chem. Phys. 2003, 118, 4183–4189. (20)

Parsons, D. F.; Ninham, B. W. Charge Reversal of Surfaces in Divalent Electrolytes: The

Role of Ionic Dispersion Interactions. Langmuir 2010, 26, 6430–6436. (21)

Ricci, M.; Spijker, P.; Voïtchovsky, K. Water-induced Correlation between Single Ions

Imaged at the Solid-Liquid Interface. Nat. Commun. 2014, 5, 4400. (22)

Park, C.; Fenter, P. A.; Sturchio, N. C.; Nagy, K. L. Thermodynamics, Interfacial

Structure, and pH Hysteresis of Rb+ and Sr2+, Adsorption at the Muscovite (001)–Solution Interface. Langmuir 2008, 24, 13993–14004. (23)

Park, C.; Fenter, P. A.; Nagy, K. L.; Sturchio, N. C. Hydration and Distribution of Ions at

the Mica-Water Interface. Phys. Rev. Lett. 2006, 97, 016101. (24)

Lee, S. S.; Fenter, P.; Nagy, K. L.; Sturchio, N. C. Monovalent Ion Adsorption at the

Muscovite (001)–Solution Interface: Relationships among Ion Coverage and Speciation, Interfacial Water Structure, and Substrate Relaxation. Langmuir 2012, 28, 8637–8650. (25)

Lee, S. S.; Fenter, P.; Park, C.; Sturchio, N. C.; Nagy, K. L. Hydrated Cation Speciation

at the Muscovite (001)–Water Interface. Langmuir 2010, 26, 16647–16651. (26)

Schlegel, M. L.; Nagy, K. L.; Fenter, P.; Cheng, L.; Sturchio, N. C.; Jacobsen, S. D.

Cation Sorption on the Muscovite (001) Surface in Chloride Solutions Using HighResolution X-ray Reflectivity. Geochim. Cosmochim. Acta 2006, 70, 3549–3565. (27)

Cheng, L.; Fenter, P.; Nagy, K. L.; Schlegel, M. L.; Sturchio, N. C. Molecular-Scale

Density Oscillations in Water Adjacent to a Mica Surface. Phys. Rev. Lett. 2001, 87, 156103.


24

Page 25 of 37

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Langmuir

(28)

Sakuma, H.; Kawamura, K. Structure and Dynamics of Water on Muscovite Mica

Surfaces. Geochim. Chosmochim. Acta 2009, 73, 4100–4110. (29)

Sakuma, H.; Kondo, T.; Nakao, H.; Shiraki, K.; Kawamura, K. Structure of Hydrated

Sodium Ions and Water Molecules Adsorbed on the Mica/Water Interface. J. Phys. Chem. C 2011, 115, 15959–15964. (30)

Fukuma, T.; Ueda, Y.; Yoshioka, S.; Asakawa, H. Atomic-Scale Distribution of Water

Molecules at the Mica-Water Interface Visualized by Three-Dimensional Scanning Force Microscopy. Phys. Rev. Lett. 2010, 104, 016101. (31)

Kimura, K.; Ido, S.; Oyabu, N.; Kobayashi, K.; Hirata, Y.; Imai, T.; Yamada, H.

Visualizaing Water Molecule Distribution by Atomic Force Microscopy. J. Chem. Phys. 2010, 132, 194705. (32)

Kobayashi, K.; Oyabu, N.; Kimura, K.; Ido, S.; Suzuki, K.; Imai, T.; Tagami, K.;

Tsukada, M.; Yamada, H. Visualization of Hydration Layers on Muscovite Mica in Aqueous Solution by Frequency-Modulation Atomic Force Microscopy. J. Chem. Phys.2013, 138, 184704. (33)

Siretanu, I.; Ebeling, D.; Andersson, M. P.; Stipp, S. L. S.; Philipse, A.; Stuart, M. C.;

Van den Ende, D.; Mugele, F. Direct Observation of Ionic Structure at Solid-Liquid Interfaces: a Deep Look into the Stern Layer. Sci. Rep. 2014, 4, 4956. (34)

Loh, S.-H.; Jarvis, S. P. Visualization of Ion Distribution at the Mica–Electrolyte

Interface. Langmuir 2010, 26, 9176–9178. (35)

Gaisinskaya-Kipnis, A.; Ma, L.; Kampf, N.; Klein, J. Frictinal Dissipation Pathways

Mediated by Hydrated Alkali Metal Ions. Langmuir 2016, 32, 4755–4764. (36)

Park, S.-H.; Sposito, G. Structure of Water Adsorbed on a Mica Surface. Phys. Rev. Lett.


25

Langmuir

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 26 of 37

2002, 89, 085501. (37)

Kobayashi, K.; Liang, Y.; Amano, K.; Murata, S.; Matsuoka, T.; Takahashi, S.; Nishi, N.;

Sakka, T. Molecular Dynamics Simulation of Atomic Force Microscopy at the Water– Muscovite Interface: Hydration Layer Structure and Force Analysis. Langmuir 2016, 32, 3608–3616. (38)

Meleshyn, A. Adsorption of Sr2+ and Ba2+ at the Cleaved Mica–Water Interface: Free

Energy Profiles and Interfacial Structure. Geochim. Cosmochim. Acta 2010, 74, 1485–1497. (39)

Meleshyn, A. Potential of Mean Force for Mg2+ at the Cleaved Mica–Water Interface. J.

Phys. Chem. C 2009, 113, 12946–12949. (40)

Meleshyn, A. Potential of Mean Force for K+ in Thin Water Films on Cleaved Mica.

Langmuir 2010, 26, 13081–13085. (41)

Meleshyn, A. Potential of Mean Force for Ca2+ at the Cleaved Mica–Water Interface. J.

Phys. Chem. C 2009, 113, 17604–17607. (42)

Richardson, S. M. Crystal Structure of a Pink Muscovite From Archer’s Post, Kenya:

Implications for Reverse Pleochroism in Dioctahedral Micas. Am. Mineral. 1982, 67, 69–75. (43)

Torrie, G. M.; Valleau, J. P. Monte Carlo Free Energy Estimates Using Non-Boltzmann

Sampling: Application to the Sub-Critical Lennard-Jones Fluid. Chem Phys. Lett. 1974, 28, 578–581. (44)

Torrie, G. M.; Valleau, J. P. Nonphysical Sampling Distributions in Monte Carlo Free-

Energy Estimation: Umbrella Sampling. J. Comput. Phys. 1977, 23, 187–199. (45)

Kӓstner, J. Umbrella Sampling. Wiley Interdiscip. Rev. Comput. Mol. Sci. 2011, 1, 932–

942.


26

Page 27 of 37

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

(46)

Beutler, T. C.; van Gunsteren, W. F. The Computation of a Potential of Mean Force:

Coice of the Biasing Potential in the Umbrella Sampling Technique. J. Chem Phys. 1994, 100, 1492–1497. (47)

Hub, J. S.; de Groot, B. L.; van der Spoel, D. g_wham–A Free Weighted Histogram

Analysis Implementation Including Robust Error and Autocorrelation Estimates. J. Chem. Theory Comput. 2010, 6, 3713–3720. (48)

Kumar, S.; Rosenberg, J. M.; Bouzida, D.; Swendsen, R. H.; Kollman, P. A. The

Weighted Histogram Analysis Method for Free-Energy Calculations on Biomolecules. I. The Method. J. Comput. Chem. 1992, 13, 1011–1021. (49)

Souaille, M.; Roux, B. Extension to the Weighted Histogram Analysis Method:

Combining Umbrella Sampling with Free Energy Calculations. Comput. Phys. Commun. 2001, 135, 40–57. (50)

Hess, B.; Kutzner, C.; van der Spoel, D.; Lindahl, E. GROMACS 4: Algorithms for

Highly Efficient, Load-Balanced, and Scalable Molecular Simulation. J. Chem. Theory Comput. 2008, 4, 435–447. (51)

Cygan, R.; Liang, J.; Kalinichev, A. Molecular Models of Hydroxide, Oxyhydroxide, and

Clay Phases and the Development of a General Force Field. J. Phys. Chem. B 2004, 108, 1255–1266. (52)

Joung, I. S.; Cheatham III, T. E. Determination of Alkali and Halide Monovalent Ion

Parameters for Use in Explicitly Solvated Biomolecular Simulation. J. Phys. Chem. B 2008, 112, 9020–9041. (53)

Åqvist, J. Ion–Water Interaction Potentials Derived from Free Energy Perturbation

Simulations. J. Phys. Chem. 1990, 94, 8021–8024.


27

Langmuir

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(54)

Page 28 of 37

Berendsen, H. J. C.; Grigera, J.; Straatsma, T. The Missing Term in Effective Pair

Potentials. J. Phys. Chem. 1987, 91, 6269–6271. (55)

Kobayashi, K.; Liang, Y.; Sakka, T.; Matsuoka, T. Molecular Dynamics Study of Salt-

Solution Interface: Solubility and Surface Charge of Salt in Water. J. Chem. Phys. 2014, 140, 144705. (56)

Essmann, U.; Perera, L.; Berkowitz, M. L.; Darden, T.; Lee, H.; Pedersen, L. G. A

Smooth Particle Mesh Ewald Method. J. Chem. Phys. 1995, 103, 8557–8593. (57)

Nose, S. A Molecular Dynamics Method for Simulations in the Canonical Ensemble.

Mol. Phys. 1984, 52, 255–258. (58)

Hoover, W. G. Canonical Dynamics: Equilibrium Phase-Space Distributions. Phys. Rev.

A 1985, 31, 1695–1697. (59)

Parrinello, M.; Rahman, A. Strain Fluctuations and Elastic Constants. J. Chem. Phys.

1982, 76, 2662–2666. (60)

Humphrey, W.; Dalke, A.; Schulten, K. VMD: Visual Molecular Dynamics. J. Mol.

Graphics 1996, 14, 33–38. (61)

Ansell, S.; Barnes, A. C.; Mason, P. E.; Neilson, G. W.; Ramos, S. X-ray and Neutron

Scattering Studies of the Hydration Structure of Alkali Ions in Concentrated Aqueous Solutions. Biophs. Chem. 2006, 124, 171–179. (62)

Bankura, A.; Carnevale, V.; Klein, M. L. Hydration Structure of Salt Solutions from ab

initio Molecular Dynamics. J. Chem. Phys. 2013, 138, 014501. (63)

Carrillo-Tripp, M.; Saint-Martin, H.; Ortega-Blake, I. A Comparative Study of the

Hydration of Na+ and K+ with Refined Polarizable Model Potentials. J. Chem. Phys. 2003, 118, 7062.


28

Page 29 of 37

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

(64)

White, J. A.; Schwegler, E.; Galli, G.; Gygi, F. The Soluvation of Na+ in Water: First-

Principles Simulations. J. Chem. Phys. 2000, 113, 4668. (65)

Allen, T. W.; Bliznyuk, A.; Rendell, A. P.; Kuyucak, S.; Chung, S.-H. The Potassium

Channel: Structure, Selectivity, and Diffusion. J. Chem. Phys.2000, 112, 8192. (66)

Degrève, L.; da Silva, F. L. B. Structure of Concentrated Aqueous NaCl Solution: A

Monte Carlo Study. J. Chem. Phys. 1999, 110, 3070–3078. (67)

Degrève, L.; de Pauli, V. M.; Duarte, M. A. Simulation Study of the Role and Structure

of Monatomic Ions Multiple Hydration Shells. J. Chem. Phys. 1997, 106, 655–665. (68)

Tóth, G. Ab initio Pair Potential Parameter Set for the Interaction of a Rigid and a

Flexible Water Model and the Complete Series of the Halides and Alkali Cations. J. Chem. Phys. 1996, 105, 5518–5524. (69)

Obst, S.; Bradaczek, H. Molecular Dynamics Study of the Structure and Dynamics of the

Hydration Shell of Alkaline and Alkaline-Earth Metal Cations. J. Phys. Chem. 1996, 100, 15677–15687. (70)

Smith, D. E.; Dang, L. X. Computer Simulations of NaCl Association in Polarizable

Water. J. Chem. Phys. 1994, 100, 3757–3766. (71)

Zhu, S.-B.; Robinson, G. W. Molecular-Dynamics Computer Simulation of an Aqueous

NaCl Solution: Structure. J. Chem. Phys. 1992, 97, 4337–4348. (72)

Cieplak, P.; Kollman, P. Monte Carlo Simulation of Aqueous Solutions of Li+ and Na+

Using Many-Body Potentials. Coordination Numbers, Ion Solvation Enthalpies, and the Relative Free Energy of Solvation. J. Chem. Phys. 1990, 92, 6761–6767. (73)

Pauling, L. The Nature of the Chemical Bond, 2nd ed.; Cornell University Press: New

York, 1948.


29

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Marcus, Y. Thermodynamics of Solvation of Ions. J. Chem. Soc. Faraday Trans. 1991,

87, 2995–2999.

Table of Contents Graphic and Synopsis


30

a

Page 31 of 37

7.7 nm

1 2 3 4 5 6 7 8 9 10 11 12

c

Langmuir

b

ACS Paragon Plus Environment 3.1 nm

2.7 nm

PMF (kJ/mol)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43

PMF (kJ/mol)

b

Langmuir

5

Page 32 of 37

0 +

-5

Na + K + Rb+ Cs

-10 -15 -20 -25

PMF

a

-30 -35

IS2

OS

IS1

D

0

0.2

0.4

0.6 0.8 D (nm)

1

1.2

20 0 -20 -40 -60 2+

Mg2+ Ca2+ Sr Ba2+

-80 -100 -120

0

0.2

0.4

0.6

0.8


D (nm)

1

1.2

Page 33 of 37

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

b

a

Langmuir

c

d


a 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35

e

Langmuir

b

f

c

g

d

h

Page 34 of 37


0.7

Page 35 of 37

Langmuir

0.6

Height (nm)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

OS

0.5 0.4

Mg2+

0.3

IS2

0.2 0.1 0

Rb+

K+ Na+ Ca

2+

Sr2+

Ba2+

2+ 2+ Sr2+ Ba Ca Mg Ba2+ + Na + + Rb 2+ K Ca Sr2+ 2+

Na+

0

Cs+

IS1

0.05 0.1 0.15 Ionic Radius (nm)


Cs+

0.2

∆GIS1-∆GIS2 (kJ/mol)

20

PageMg 36 of 37 2+

Langmuir

Ca2+

15 Sr2+

10 5 0 -5 -10

Na+

Ba2+

～～

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17

Cs+ Rb+ K+

～～

25

0

0.5

1

1.5 2 2.5 q/rx (e/ Å )

ACS Paragon Plus 3 Environment 3

7

7.5

Potential of Mean Force of Cation

Page 37 of 37

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

IS1

OS (monovalent cations)

IS2

OS (divalent cations)

Langmuir

IS: Inner-sphere surface complex OS: Outer-sphere surface complex

OS

IS2 IS1 ACS Paragon Plus Environment Ion-Muscovite Surface Distance

H

O

Al

Si

Cation

Ion Distribution and Hydration Structure in the Stern Layer on

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