Interactions Between Hydrated Calcium Carbonate Surfaces at

Article Cite This: J. Phys. Chem. C XXXX, XXX, XXX−XXX

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Interactions Between Hydrated Calcium Carbonate Surfaces at Nanoconfinement Conditions Gøran Brekke-Svaland* and Fernando Bresme* Department of Chemistry, Imperial College London, London, SW7 2AZ, United Kingdom S Supporting Information *

ABSTRACT: Calcium carbonate is one of the most abundant minerals on Earth and a component of natural biogenic materials and man-made cements. The interactions between hydrated calcium carbonate surfaces at nanometer confinement are relevant in dissolution and crystallization processes as well as in adsorption of organic fluids in natural reservoirs. In this work we quantify using atomistic molecular dynamics simulations the water mediated interactions between calcium carbonate surfaces at nanometer separations. We investigate two calcium carbonate polymorphs, calcite and aragonite. We show that the adsorption behavior of water on the (101̅4) surface of calcite and the (001) surface of aragonite is very different. These differences are reflected in intersurface forces between the two mineral surfaces. The interactions between surfaces feature an oscillatory behavior whose origin is connected to the structuring of water at an intersurface separation 10 Å the liquid reaches the bulk

Figure 3. Density profiles of water under confinement as a function of the mineral surface-to-surface separation, D. Results for calcite (cal) and aragonite (ara) are shown. “in” and “out” indicate whether the surfaces are “in” or “out” of registry. “out1” corresponds to 1/2 lattice out of registry. The vertical dashed lines show the position of the Ca2+ plane in the mineral surface. Horizontal dashed lines indicate bulk density of water. D

DOI: 10.1021/acs.jpcc.8b01557 J. Phys. Chem. C XXXX, XXX, XXX−XXX

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The Journal of Physical Chemistry C

insensitive to the degree of confinement. The orientational profile shows that the dipole moment vector of the water molecules located below the maximum in the density peak, i.e., in direct contact with the mineral surfaces, is lying flat on the surface, for both calcite and aragonite (Tp = −0.35). Instead the water molecules lying above the maximum, i.e., in direct contact with water, have their dipole moments pointing parallel to the vector normal to the mineral surface. Figures S3 and S4 offer a more detailed view of the orientations of the water molecules in the first solvation layer, highlighting the different orientational preference of water molecules in direct contact with the mineral or other water molecules. The water molecules in the first solvation layer have three main orientations, comparable to the results obtained by Mutisya et al.49 The ordering beyond the first solvation shell and its dependence with the degree of confinement depends on the mineral surface. We observe that the “in”/“out” of registry effects are more prominent in aragonite than calcite. The snapshots (see Figure 2) and the density and orientation profiles (Figures 2 and 3) show that the lateral displacement of the surfaces influences the structure of the liquid at high confinement conditions. We showed above that the “in”/“out”

Figure 4. Orientational order parameter Tp in the confined region as a function of the surface-to-surface separation, D, for calcite (cal) and aragonite (ara). We show results for the “in” and 1/2 lattice “out” of registry cases. The vertical dashed lines represent the position of Ca2+ plane in the crystal surface.

Figure 5. Two dimensional density profiles of water for different solvation layers, SN (see Figure S1). Panel A represents data for aragonite (left) and calcite (right), respectively. The two upper-left figures in this panel show the ordering of Ca2+ ions in both mineral surfaces. The white circles in the main panels represent the Ca2+ ions. Panel B shows the density profiles for an intersurface distance of 7.5 Å. Panels C and D show the profiles for this distance but for cases “out1” and “out2″, respectively. SNU/L, indicate the solvation layers corresponding to the upper and lower surfaces. The thickness of the sampled region of the solvation layers S1 and S2 was 1.5, 1.0 Å for calcite and 1.5, 1.3 Å for aragonite, respectively. E


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matching that leads to the double peak observed in the density profile in Figure 3. Moving the surfaces out registry influences significantly the structure of water confined between aragonite surfaces, enhancing the in-plane delocalization of the water molecules (see Figure 5C) for the “out1”. Water localization in lattice sites can be recovered by taking the surfaces out of registry again, see “out2” in Figure 5D. In comparison, the relative displacement of the calcite surfaces (see Figure 5C,D) has a minor impact on the structure of water, and the checkerboard pattern is preserved to a large extent in both cases. Overall, our results show that the solvation structure of calcite is much less sensitive to confinement conditions or relative surface separation than the aragonite one. In fact, for the conditions considered here the solvation structure of water on calcite is surprisingly resilient, even for intersurface separations of D = 7.5 Å, which correspond to two water layers on each surface in direct contact. We examine in the next section the impact that the changes in the solvation structure has on the surface forces. Surface Forces. The surface forces at close intersurface separations influence significantly the adsorption and structure of water in the nanogap separating the mineral surfaces. The adsorption of water in the nanogap was obtained by calculating the average number of water molecules in the confinement region. We checked the consistency of this approach by calculating the number of water molecules from the integral of the density profiles (see Figure 3). The solvation and the slab−slab forces were averaged and divided by the surface area of the confined region for 27 separations. We used a grid of 0.5 Å to resolve the oscillatory behavior of the forces at high confinement. A larger increment of 1.0 Å was used for separations >14 Å. The simulations were run until the number of water molecules in the confined region reached the stationary state, i.e., dN/dt ≈ 0 (see Figures S5 and S6 in Supporting Information). We show in Figure 6 the number of excess water molecules Nexcess(D), defined as the difference between the number of water molecules at separation D, Nc(D), and the limiting amount, Nl(D), of water between the surfaces at long distances, where confinement effects can be neglected. The limiting

of registry effects are more important in the aragonite case. When the aragonite surfaces are shifted half a lattice out of registry, the carbonates in the upper surface are located directly above the carbonates in the lower surface. The water molecules in the second solvation layer will therefore interact with both carbonate planes. These interactions result in a less homogeneous lateral ordering of water, with the formation of small “cavities”, where water is not present (see Figure 2). We also find this lateral inhomogeneous structure in the “out2” case. Advancing the discussion below, the relative displacement of the surfaces also influences the amount of water adsorbed in the confined region and consequently the surface forces. Unlike in aragonite, the lateral displacement of the calcite surfaces has a much smaller impact on the general structure of the adsorbed water (see Figure 2). In particular, the general checkerboard pattern formed in the solvation layers on the calcite surface is preserved in all cases, indicating that the sliding of calcite surfaces relative to each other has a minor impact on the solvation structure. To analyze the adsorption patterns of water on calcite (101̅4) and aragonite (001), we computed two-dimensional density profiles for different solvation planes (see Figure 5). The analysis of the profiles at large intersurface separations, i.e., when there is no overlap between solvation layers, shows that the water molecules in contact with the calcite surface adsorb preferentially on top of the Ca2+ ions, while the water molecules in the second layer are located in the middle of the rectangular patterns formed by these ions. The solvation pattern resembles the structure reported by Stipp et al.21 and more recently by Söngen et al.9 using the FM-AFM apparatus. This structure has also been reported in previous computational studies.14,48 Calcite imposes a strong lateral order on water, which is transmitted into the liquid, up to the third solvation layer (S3). In contrast, the structure of the third layer above the aragonite surface is homogeneous. We expect the lack of strong ordering might be connected to the position of the water molecules on the aragonite surface, which does not match that of the Ca2+ ions. Indeed, there is a mismatch between the layer of Ca2+ ions and the first water layer, with the water molecules occupying interstitial positions between the Ca2+ ions and forming an irregular triangular pattern. A certain degree of mismatch is expected since the outermost layer of aragonite (001) is populated by carbonate ions. Unlike calcite, the second solvation layer of aragonite has a significant loss of orientational order, and no clear regular pattern can be identified either. How does the conf inement and degree of surface registry inf luence the solvation pattern? We can address this question using the information contained in the panels B−D represented in Figure 5. We find that water molecules in direct contact with the surface reproduce, at the highest level confinement considered here (D = 7.5 Å), the same pattern observed for large distances, irrespective of the mineral, either aragonite or calcite. This result is consistent with our calculations of density and orientational order parameter profiles (see Figures 3 and 4). The second solvation layer of calcite shows strong ordering and preserves the main structure compatible with the checkerboard pattern (c.f. Figure 5, panels A and B). For aragonite the structural perturbation due to confinement is clear. Under confinement the water molecules become laterally delocalized, as illustrated by the formation of distinctive “bands” of high density (see Figure 5B) and high kinetic mobility. The bands of the upper and lower surfaces do not lie on top of each other showing lack of a good geometric

Figure 6. Number of excess water molecules in the nanogap as a function of the intersurface separation, D. Data for “out1” and “out2” correspond to the 1/2 and 3/4 out of registry configurations. The number of excess water molecules for the aragonite systems are shifted upward by 25 molecules to facilitate the comparison of the data. Horizontal dashed lines correspond to Nexcess = 0. F


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Figure 7. Disjoining pressures of the “in” (left) and “out” of registry (right) configurations for calcite (cal) and aragonite (ara), as a function of intersurface separation, D. Open squares represent data from the external load simulations. Dashed lines join the points obtained using the fixed surface separation method. Data for “out1” and “out2” refer to 1/2 and 3/4 lattice out of registry configurations, respectively.

The results obtained with this procedure (see “ext.load” data in Figure 7-left) confirm our results and the consistency of both simulation approaches. The existence of the adhesive minimum is reflected in a discontinuous jump under normal load (see Figure 7) as the normal load method only samples “repulsive” branches. We do not expect the adhesive minima to be an artifact of edge effects as we reproduced the same results with extended surfaces (see Figure S9 in the Supporting Information). We also reproduced with the normal load approach the main repulsive branch of the Π(D) of aragonite. Our simulations showed that for repulsive branches at lower pressures (see Π(D) of aragonite between 10 and 11 Å) it was possible to observe a discontinuous jump at a lower pressure than that obtained with the fixed surface separation. The harmonic spring attached to the upper surface allows a lateral displacement, which means that we can sample different disjoining pressure profiles according to epitaxial effects. This implies that the free energy profile of the surface-to-surface separation of calcite (101̅4) is less prone to be influenced by epitaxial effects than the aragonite (001) surface. Our simulations also show that the surfaces are likely to remain solvated at very high pressures. As a matter of fact at ∼1 GPa, the surfaces of calcite and aragonite are fully solvated with two and three solvation layers, respectively (see D = 7.5, 8.5 Å in Figure 3). The results discussed above show similarities in the disjoining pressures of calcite and aragonite, such as the existence of adhesive minima and at short separations, strong repulsive pressures, connected to the overlap of solvation layers. At the same time differences are observed, such as the relative shift along D in the disjoining pressure, which highlights the importance of the mineral surface structure as template for the structuring of the solvation layers. To analyze the impact of the surface structure in more detail, we analyzed the dependence of the disjoining pressure on the registry of the surfaces. Taking the surfaces out of registry has a major influence on the disjoining pressure. The adhesive minima becomes less negative for both calcite and aragonite. In the later case it is even possible to eliminate almost entirely the adhesive minimum (see “out1” case for aragonite in Figure 7-right panel, at D = 0.8−0.9 nm, Π is reduced by 92% when the surfaces are shifted 1/2 lattice out of registry). The relative displacement of the surfaces can disrupt significantly the oscillatory behavior of the

amount increases linearly with intersurface separation following a linear function Nl(D) = ξD + Nad, where Nad is a constant. To obtain ξ we fitted Nc(D) in the range D = 2−3 nm, where confinement effects are not relevant. We show in Figure 6 the excess of water molecules as a function of D. At close interfacial separations, oscillations in the Nexcess are observed. For the closest separations, < 10 Å, water molecules are no longer squeezed out of the confined region, and a large increase in the excess number of water molecules relative to bulk value is observed. This is consistent with the fact that the water molecules next to the mineral surfaces cannot be expelled at short separations. The registry effects (c.f. “out1″, “out2” and “in” cases in Figure 6) are only relevant at the shortest separations where Nexcess features some variability across the different epitaxial cases. Overall, the results for Nexcess indicate that the confinement and epitaxial effects are not important beyond D ≈ 13 Å. We therefore expect that the disjoining pressure will be zero beyond this distance too. We examine the results from the surface forces in the following. We show in Figure 7 the disjoining pressure obtained from the simulations at constant intersurface separation. We have also added the results for specific systems using the external load (ext. load) simulations, as well as disjoining pressures Π(D) for the “in” and “out” of registry configurations. The disjoining pressure of the “in registry” configurations features a characteristic oscillatory behavior at short intersurface separations, which is connected to the existence of solvation layers induced by the surfaces. The minima in calcite/aragonite feature a wavelength of ∼2.5 and 2.0 Å, shorter than the approximate diameter of the water molecule (∼3 Å), showing that the layering is not determined exclusively by packing effects, unlike what has been observed before in simple fluids.11 The disjoining pressure converges to zero at distances larger than D ≈ 13 Å, showing that the confinement effects are not relevant beyond this intersurface distance. An interesting feature of Π(D), both for calcite and aragonite, is the existence of a strong negative pressure at D ≈ 8 and 8.9 Å respectively. The minima correlates with the onset of a transition from 5 → 4/4 → 3 solvation layers of calcite/aragonite surfaces (see D = 7.5−9.5 Å in Figure 3). In an experiment the presence of this minimum would translate to a state of adhesion. To test the reproducibility of our results we performed additional computations by applying a normal load to one of the slabs. G


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The Journal of Physical Chemistry C disjoining pressure (see “out1” for aragonite, Figure 7 right panel). We have calculated the free energy or work required to approach/separate the solvated mineral surfaces by using eq 3 and the disjoining pressure. We show in Figure 8 the free

parameter) is of particular interest, as it features a free energy that is completely repulsive, due to the loss of oscillatory behavior in the disjoining pressure (see Figure 7). This interaction is completely different from the one observed in the “in” registry case. The relative displacement of the surfaces can also have a large influence on the free energy of calcite. The adhesion free energy (defined as the primary minimum in the free energy curve) decreases from −53 mJ m−2 to −14 mJ m−2 for the “in” and “out2” configurations, respectively. These results highlight the importance that the type of mineral surface and the relative shift between the surfaces has in determining the effective interaction between the minerals. When the system is allowed to relax, we expect it will adopt the configuration corresponding to the global minimum in the free energy profile. The free energy of adhesion that we have computed in our simulations for calcite is different from the experimental results (see Røyne et al.,18 Diao and Espinosa-Marzal19) who concluded that the forces between calcite surfaces in water are purely repulsive. It was concluded in one of these works18 that the repulsion was connected to the hydration layers coating the calcite surfaces. This idea is consistent with the strong repulsion we observe at short distances. It follows from our simulations that the strongly hydrated surfaces can feature significant adhesion, although the latter can be modulated and weakened by shifting the relative position of the surfaces. Previous works on water confined between amorphous calciumsilicate-hydrate nanoparticles reported adhesive minima in the interaction free energy that are of the same order as those reported here Yu and Lau.50 Hence, our observations could apply to other systems involving water under nanoconfinement conditions.

Figure 8. Free energy as a function of separation between mineral surfaces for the “in” and “out” of registry configuration of calcite and aragonite.

energy as a function of intersurface separation for the “in” and “out” of registry configurations. Numerical results for the maxima and minima in the free energy curves as a function of the intersurface separation are compiled in Table 1. Following Table 1. Free Energy Maxima and Minima for Calcite and Aragonite “in” and 3/4 Lattice “out” of Registry (see Figure 8) calcite “in” registry D [Å] 7.7 9.2 10.2

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aragonite “in” registry −2

F [mJ m ] −53(4) 5(3) −5(3) calcite “out2” −2

D [Å]

F [mJ m−2]

8.3 9.8

−50(2) 4(2) aragonite “out2”

D [Å]

F [mJ m ]

D [Å]

7.7 9.2 10.2

−14(4) 4(2) −11(3)

8.2 9.4

CONCLUSIONS

We have investigated using molecular dynamics simulation the interactions between hydrated calcium carbonate surfaces as a function of intersurface separation. We considered two polymorphs, calcite and aragonite. The former is the stable phase at standard conditions, while aragonite appears in calcifying organisms as a precursor to calcite. We have investigated the modification of the structure of liquid water induced by the mineral surface and confinement at nanometer length-scales, and we have quantified the dependence of the surface forces on the degree of confinement and composition of the mineral surface, addressing epitaxial effects. Our results provide molecular insight into the origin of the solvation forces, and therefore it might be relevant to interpret recent experimental studies of intersurface forces using the surface forces apparatus or the atomic force microscope. We draw the following conclusions from our work: • The simulations confirm the formation of a checkerboard pattern of water adsorbed on calcite, in agreement with previous FM-AFM experiments and simulations. The solvation structure of water on calcite, including the orientation of the water molecules, is preserved at fairly short intersurface separations, ∼9.5 Å, i.e., about three water molecular diameters. A similar conclusion applies to aragonite surfaces, although the solvation structure is very different from that of calcite. Calcite imposes a stronger lateral order in the water molecules, which extends up the third solvation layer from the surface. Our structural analyses demonstrate that the water molecules

F [mJ m−2]

the disjoining pressure results, the free energies of the “in” registry configurations feature a prominent attractive well. The free energy minimum of aragonite is shifted to longer distances as compared with that of calcite, and it is slightly more shallow in energy. For calcite “in” registry, we observe three maxima in the free-energy profiles at approximately two times the distance to the second and third peaks in the density profile, corresponding to 6.73(9) to 9.41(8) Å respectively. Two times the distance to the fourth peak in the water density profile on the (1014̅ ) calcite surface is 14.6(1) Å. This distance does not fit with where we observe the corresponding peak in the free energy and the disjoining pressure profiles. For aragonite “in” registry, the distances corresponding to two times the distance to the second and third peak in the density profile correspond to 8.4(1) and 15.6(2) Å respectively. The impact of registry on the interactions between the surfaces is also reflected in the free energies. The “out1” case (corresponding to a relative shift of 1/2 in the lattice H


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depends on the structure of the mineral surface and epitaxial effects. These conclusions should be relevant to understand mineral aggregation in solution, biomineralization processes, and wettability in nanopores. Future studies will focus on ionic solutions under confinement conditions.

next to aragonite surfaces feature a higher mobility than in calcite, and generally the translational order is less strong and the distribution of the water molecules is less homogeneous too. • We investigated the importance of epitaxial effects on the solvation structure. To address this effect we shifted the mineral surfaces out of registry with respect to each other. Registry effects are found to be more important in aragonite than in calcite. At very high confinement the solvation layers in aragonite merge with each other. In calcite, however, the checkerboard pattern of surface water is preserved in the out of registry cases. This result indicates that the sliding of a calcite surface relative to each other has a minor impact on the solvation structure. Overall, we found that the hydration layers of calcite are less sensitive to confinement conditions than the aragonite one. • The surface forces feature a characteristic oscillatory behavior that dies away at about 13 Å separation. This decay length correlates well with what is expected on the basis of SFA experimental studies, where steps in the force-separation curve have been reported before. The simulations also show a significant repulsion force at short distances, whose origin is connected to the interaction between the hydration layers. This result supports observations based on AFM experiments, which concluded that the repulsion is likely connected to the hydration of the hydrophilic calcite surface. Our simulations confirm the validity of these conclusions. We found that the surfaces maintain the solvation layers at very high disjoining pressures, ∼ 1 GPa. • We have also shown that the surface forces feature a prominent adhesive minimum at ∼8 Å and ∼9 Å for calcite and aragonite surfaces, respectively. The adhesive minimum corresponds to the transition from 5 → 4, 4 → 3 solvation layers in the confined region of calcite and aragonite, respectively. Previous SFA and AFM experiments did not report adhesive minima for calcite. Possible sources of differences between the simulations and experiments could be salinity conditions, degree of roughening of the calcite surfaces in experiments or epitaxial effects, which could be captured in the experiment by using large surfaces. Our analysis of the epitaxial effects via simulations of surfaces with different registry indicates that epitaxy might play an important role in determining the observation of adhesive minima. We found that the intensity of the latter is reduced in both calcite and aragonite, and in aragonite it is even possible to eliminate the adhesion completely. Indeed, we observed purely repulsive free energies between aragonite surfaces, when the surfaces are not in registry. Another factor that could prove to be important in these confined systems is the presence of other ions in the solution. Overall, our work provides a molecular level understanding of the origin of the interactions between hydrated calcium carbonate surfaces at nanometer confinement. These results validate previous conclusions based on AFM experiments, highlighting the importance of the solvation layers on mineral surfaces in defining strong repulsion at short separations. Our simulations also predict adhesive minima between calcium carbonate surfaces solvated with water and show that adhesion

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ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.jpcc.8b01557. The Supporting Information includes details in the forcefields employed in the simulations, tables on structural data, additional density and orientational profiles, adsorption of water in the confined region as a function of time and molecular structures of calcite and aragonite. (PDF)

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AUTHOR INFORMATION

Corresponding Authors

*(G.B.-S.) E-mail: [email protected]. *(F.B.) E-mail: [email protected]. ORCID

Gøran Brekke-Svaland: 0000-0002-3172-746X Fernando Bresme: 0000-0001-9496-4887 Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS This work has been funded by the project NanoHeal, which is part of the European Union’s Horizon 2020 research and innovation programme, under Grant Agreement No. 642976. We thank Imperial College High Performance Computing Service for providing computational resources. We thank Juan D. Olarte Plata for many helpful discussions.

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REFERENCES

(1) World Business Council for Sustainable Development; International Energy Agency, Cement Technology Roadmap 2009: Carbon Emissions Reductions Up To 2050; 2009; p 36. (2) Amanto, I. Green Cement: Concrete Solutions. Nature 2013, 494, 300−301. (3) Uwasu, M.; Hara, K.; Yabar, H. World Cement Production and Environmental Implications. Environ. Dev. 2014, 10, 36−47. (4) Morse, J. W.; Arvidson, R. S.; Lüttge, A. Calcium Carbonate Formation and Dissolution. Chem. Rev. 2007, 107, 342−381. (5) Cartwright, J. H. E.; Checa, A. G.; Gale, J. D.; Gebauer, D.; SainzDiaz, C. I. Calcium Carbonate Polymorphism and Its Role in Biomineralization: How Many Amorphous Calcium Carbonates Are There? Angew. Chem., Int. Ed. 2012, 51, 11960−11970. (6) Millero, F. J. Thermodynamics of the Carbon Dioxide System in the Oceans. Geochim. Cosmochim. Acta 1995, 59, 661−677. (7) Ricci, M.; Spijker, P.; Stellacci, F.; Molinari, J. F.; Voitchovsky, K. Direct Visualization of Single Ions in the Stern Layer of Calcite. Langmuir 2013, 29, 2207−2216. (8) Geissbühler, P.; Fenter, P.; DiMasi, E.; Srajer, G.; Sorensen, L. B.; Sturchio, N. C. Three-Dimensional Structure of the Calcite-Water Interface by Surface X-Ray Scattering. Surf. Sci. 2004, 573, 191−203. (9) Söngen, H.; Nalbach, M.; Adam, H.; Kühnle, A. ThreeDimensional Atomic Force Microscopy Mapping at the Solid-Liquid Interface With Fast and Flexible Data Acquisition. Rev. Sci. Instrum. 2016, 87, 063704. (10) Israelachvili, J. Solvation Forces and Liquid Structure, as Probed By Direct Force Measurements. Acc. Chem. Res. 1987, 20, 415−421.

I


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The Journal of Physical Chemistry C (11) Gao, J.; Luedtke, W. D.; Landman, U. Origins of Solvation Forces in Confined Films. J. Phys. Chem. B 1997, 101, 4013−4023. (12) O’Shea, S. J.; Gosvami, N. N.; Lim, L. T. W.; Hofbauer, W. Liquid Atomic Force Microscopy: Solvation Forces, Molecular Order, and Squeeze-Out. Jpn. J. Appl. Phys. 2010, 49, 08LA01. (13) Teng, H. H.; Dove, P. M.; De Yoreo, J. J. Kinetics of Calcite Growth: Surface Processes and Relationships to Macroscopic Rate Laws. Geochim. Cosmochim. Acta 2000, 64, 2255−2266. (14) Raiteri, P.; Gale, J. D.; Quigley, D.; Rodger, P. M. Derivation of an Accurate Force-Field for Simulating the Growth of Calcium Carbonate From Aqueous Solution: A New Model For the CalciteWater Interface. J. Phys. Chem. C 2010, 114, 5997−6010. (15) Helm, C. A.; Israelachvili, J. N.; McGuiggan, P. M. Molecular Mechanisms and Forces Involved in the Adhesion and Fusion of Amphiphilic Bilayers. Science (Washington, DC, U. S.) 1989, 246, 919− 22. (16) van Megen, W. J.; Snook, I. K. Solvation Forces in Simple Dense Fluids. II. Effect of Chemical Potential. J. Chem. Phys. 1981, 74, 1409− 1411. (17) Snook, I. K.; van Megen, W. Solvation Forces in Simple Dense Fluids. I. J. Chem. Phys. 1980, 72, 2907. (18) Røyne, A.; Dalby, K. N.; Hassenkam, T. Repulsive Hydration Forces Between Calcite Surfaces and Their Effect On the Brittle Strength of Calcite-Bearing Rocks. Geophys. Res. Lett. 2015, 42, 4786− 4794. (19) Diao, Y.; Espinosa-Marzal, R. M. Molecular Insight Into the Nanoconfined Calcite-Solution Interface. Proc. Natl. Acad. Sci. U. S. A. 2016, 113, 12047−12052. (20) Lim, R.; Li, S. F. Y.; O'Shea, S. J. Solvation Forces Using Sample-Modulation Atomic Force Microscopy. Langmuir 2002, 18, 6116−6124. (21) Stipp, S. L. S.; Eggleston, C. M.; Nielsen, B. S. Calcite Surface Structure Observed at Microtopographic and Molecular Scales with Atomic Force Microscopy (AFM). Geochim. Cosmochim. Acta 1994, 58, 3023−3033. (22) Bonnaud, P. A.; Labbez, C.; Miura, R.; Suzuki, A.; Miyamoto, N.; Hatakeyama, N.; Miyamoto, A.; Van Vliet, K. J. Interaction Grand Potential Between Calcium-Silicate-Hydrate Nanoparticles at the Molecular Level. Nanoscale 2016, 8, 4160−4172. (23) Manzano, H.; Durgun, E.; López-Arbeloa, I.; Grossman, J. C. Insight on Tricalcium Silicate Hydration and Dissolution Mechanism from Molecular Simulations. ACS Appl. Mater. Interfaces 2015, 7, 14726−14733. (24) de Leeuw, N. H.; Parker, S. C. Surface Structure and Morphology of Calcium Carbonate Polymorphs Calcite, Aragonite, and Vaterite: An Atomistic Approach. J. Phys. Chem. B 1998, 102, 2914−2922. (25) Demichelis, R.; Raiteri, P.; Gale, J. D.; Quigley, D.; Gebauer, D. Stable Prenucleation Mineral Clusters are Liquid-Like Ionic Polymers. Nat. Commun. 2011, 2, 590. (26) Reischl, B.; Raiteri, P.; Gale, J. D.; Rohl, A. L. Can Point Defects in Surfaces in Solution be Atomically Resolved by Atomic Force Microscopy? Phys. Rev. Lett. 2016, 117, 226101. (27) De La Pierre, M.; Raiteri, P.; Stack, A. G.; Gale, J. D. Uncovering the Atomistic Mechanism for Calcite Step Growth. Angew. Chem., Int. Ed. 2017, 56, 8464−8467. (28) Xiao, S.; Edwards, S. A.; Gräter, F. A New Transferable Forcefield for Simulating the Mechanics of CaCO3 Crystals. J. Phys. Chem. C 2011, 115, 20067−20075. (29) Pavese, A.; Catti, M.; Parker, S. C.; Wall, A. Modelling of the Thermal Dependence of Structural and Elastic Properties of Calcite, CaCO3. Phys. Chem. Miner. 1996, 23, 89−93. (30) Pavese, A.; Catti, M.; Price, G.; Jackson, R. Interatomic Potentials for CaCO3 Polymorphs (Calcite and Aragonite), Fitted to Elastic and Vibrational Data. Phys. Chem. Miner. 1992, 19, 80−87. (31) Lee, S.; Brekke-Svaland, G.; Bresme, F. Plastic deformation and twinning mechanisms in magnesian calcites: a non-equilibrium computer simulation study. Phys. Chem. Chem. Phys. 2018, 20, 1794−1799.

(32) de Leeuw, N. H.; Parker, S. C. Atomistic Simulation of the Effect of Molecular Adsorption of Water On the Surface Structure and Energies of Calcite Surfaces. J. Chem. Soc., Faraday Trans. 1997, 93, 467−475. (33) Fenter, P.; Kerisit, S.; Raiteri, P.; Gale, J. D. Is the Calcite-Water Interface Understood? Direct Comparisons of Molecular Dynamics Simulations With Specular X-Ray Reflectivity Data. J. Phys. Chem. C 2013, 117, 5028−5042. (34) Tracey, J.; Miyazawa, K.; Spijker, P.; Miyata, K.; Reischl, B.; Canova, F. F.; Rohl, A. L.; Fukuma, T.; Foster, A. S. Understanding 2D Atomic Resolution Imaging of the Calcite Surface in Water by Frequency Modulation Atomic Force Microscopy. Nanotechnology 2016, 27, 415709. (35) Reischl, B.; Watkins, M.; Foster, A. S. Free Energy Approaches for Modeling Atomic Force Microscopy in Liquids. J. Chem. Theory Comput. 2013, 9, 600−608. (36) Fukuma, T.; Reischl, B.; Kobayashi, N.; Spijker, P.; Canova, F. F.; Miyazawa, K.; Foster, A. S. Mechanism of Atomic Force Microscopy Imaging of Three-Dimensional Hydration Structures at a Solid-Liquid Interface. Phys. Rev. B: Condens. Matter Mater. Phys. 2015, 92, 155412. (37) De La Pierre, M.; Raiteri, P.; Gale, J. D. Structure and Dynamics of Water at Step Edges on the Calcite {101 4̅} Surface. Cryst. Growth Des. 2016, 16, 5907−5914. (38) Orr, J. C.; Fabry, V. J.; Aumont, O.; Bopp, L.; Feely, R. A.; Doney, S. C.; Gnanadesikan, A.; Gruber, N.; Ishida, A.; Joos, F.; et al. Anthropogenic Ocean Acidification Over the Twenty-First Century and Its Impact on Calcifying Organisms. Nature 2005, 437, 681−686. (39) Berendsen, H. J. C.; Grigera, J. R.; Straatsma, T. P. The Missing Term in Effective Pair Potentials. J. Phys. Chem. 1987, 91, 6269−6271. (40) Wu, Y.; Tepper, H. L.; Voth, G. A. Flexible Simple Point-Charge Water Model with Improved Liquid-State Properties. J. Chem. Phys. 2006, 124, 024503. (41) Vega, C.; Abascal, J. L. F. Simulating Water With Rigid NonPolarizable Models: a General Perspective. Phys. Chem. Chem. Phys. 2011, 13, 19663. (42) Raiteri, P.; Demichelis, R.; Gale, J. D. Thermodynamically Consistent Force Field for Molecular Dynamics Simulations of Alkaline-Earth Carbonates and Their Aqueous Speciation. J. Phys. Chem. C 2015, 119, 24447−24458. (43) Raiteri, P.; Gale, J. D. Water Is the Key to Nonclassical Nucleation of Amorphous Calcium Carbonate. J. Am. Chem. Soc. 2010, 132, 17623−17634. (44) Bano, A. M.; Rodger, P. M.; Quigley, D. New Insight into the Stability of CaCO3 Surfaces and Nanoparticles via Molecular Simulation. Langmuir 2014, 30, 7513−21. (45) Hockney, R. W.; Eastwood, J. W. Computer Simulation Using Particles; CRC Press, 1989. (46) Yeh, I.-C.; Berkowitz, M. L. Ewald Summation for Systems With Slab Geometry. J. Chem. Phys. 1999, 111, 3155−3162. (47) Plimpton, S. Fast Parallel Algorithms for Short-Range Molecular Dynamics. J. Comput. Phys. 1995, 117, 1−19. (48) Hofmann, S.; Voïtchovsky, K.; Spijker, P.; Schmidt, M.; Stumpf, T. Visualising the Molecular Alteration of the Calcite (104) Water Interface by Sodium Nitrate. Sci. Rep. 2016, 6, 21576. (49) Mutisya, S. M.; Kirch, A.; de Almeida, J. M.; Sánchez, V. M.; Miranda, C. R. Molecular Dynamics Simulations of Water Confined in Calcite Slit Pores: An NMR Spin Relaxation and Hydrogen Bond Analysis. J. Phys. Chem. C 2017, 121, 6674−6684. (50) Yu, Z.; Lau, D. Nano- and Mesoscale Modeling of Cement Matrix. Nanoscale Res. Lett. 2015, 10, 173.

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