Atomic-Scale 3D Local Hydration Structures Influenced by Water

Subscriber access provided by Kaohsiung Medical University

Interfaces: Adsorption, Reactions, Films, Forces, Measurement Techniques, Charge Transfer, Electrochemistry, Electrocatalysis, Energy Production and Storage

Atomic-Scale 3D Local Hydration Structures Influenced by Water-Restricting Dimensions Kenichi Umeda, Kei Kobayashi, Taketoshi Minato, and Hirofumi Yamada Langmuir, Just Accepted Manuscript • DOI: 10.1021/acs.langmuir.8b01340 • Publication Date (Web): 09 Jul 2018 Downloaded from http://pubs.acs.org on July 24, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 31 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

1

Atomic-Scale

3D

Local

2

Water-Restricting Dimensions

Hydration

Structures

Influenced

by

3 4

Kenichi Umeda1,3,4, Kei Kobayashi1, Taketoshi Minato2, and Hirofumi Yamada1

5 6

1

7 8

Kyoto University, Katsura, Nishikyo, Kyoto 615-8510, Japan. 2

9 10

13

Office of Society-Academia Collaboration for Innovation, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510, Japan.

3

11 12

Department of Electronic Science and Engineering,

Department of Advanced Material Science, The University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba, 277-8561, Japan.

4

Nano Life Science Institute, Institute for Frontier Science Initiative, Kanazawa University, Kakuma, Kanazawa, Ishikawa, 920-1192, Japan.

14 15

Prof. Hirofumi Yamada (corresponding author)

16

Department of Electronic Science and Engineering, Kyoto University

17

E-mail: [email protected]

18 19

/ 31Environment ACS Paragon 1Plus

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

20 21

Hydration structures at solid–liquid interfaces mediate between the atomic-level

22

surface structures and macroscopic functionalities in various physical, chemical,

23

and biological processes. Atomic-scale local hydration measurements have been

24

enabled by ultra-low noise 3D frequency-modulation atomic force microscopy.

25

However, for their application to complicated surface structures, e.g., biomolecular

26

devices, understanding the relationship between the hydration and surface

27

structures is necessary. Herein, we present a systematic study based on the concept

28

of the structural dimensionality, which is crucial in various scientific fields. We

29

performed 3D measurements and molecular dynamics simulations with silicate

30

surfaces that allow for zero, one, and two degrees of freedom to water molecules.

31

Consequently, we found that the 3D hydration structures reflect the structural

32

dimensions, and the hydration contrasts decrease with increasing dimension due to

33

the enlarged water self-diffusion coefficient and increased embedded hydration

34

layers. Our results provide guidelines for the analysis of complicated hydration

35

structures, which will be exploited in extensive fields.

36


Page 2 of 31

Page 3 of 31 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

37

Langmuir

INTRODUCTION

38

Next-generation technology for the creation of sustainable energy requires the exploitations of

39

various energy-efficient phenomena at the solid–liquid interfaces, such as electrochemical,1,2

40

catalytic,3 and biological4,5 processes. To characterize such functionalities based on the surface

41

structures,6,7 the concept of dimensionality is crucial across extensive fields, e.g., quantum

42

mechanics,8 material science,9 and energy storage.2 Since local hydration structures mediate

43

between the atomic-scale surface structures and macroscopic functional phenomena, the

44

relationship between the lateral translational degrees of freedom (tDOF) afforded to water

45

molecules by the surface structural dimension and the formation of hydration structures must be

46

understood clearly. Although the interfacial hydration structures have already been studied

47

extensively with X-ray/neutron reflectivity measurements,10,11 atomic resolution has not been

48

achieved.

49

Emerging high-resolution 3D frequency-modulation atomic force microscopy (FM-AFM) has

50

been successful in elucidating the relationship between the physical properties and atomic-scale

51

hydration structures.12-20 In previous studies,12,21 we established a fast and nondestructive

52

observation protocol that could be applied to any uneven biological surfaces. We also revealed that,

53

via exploiting a heterosurface, the lateral periodicities are reflected in the lateral periodicities of the

54

hydration structures.12 Namely, the horizontal movements of the water molecules near the charged

55

surface are restricted by electrostatic interactions and the surface corrugation, which are the origin

56

of the hydration features observed with 3D FM-AFM. Therefore, we need to gain insight into the / 31Environment ACS Paragon 3Plus

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

57

relationship between the local hydration structures and surface structural dimensions for the

58

applications to functional devices. Understanding of the relationship is also important in terms of

59

the imaging mechanisms of the atomic-scale contrast in the FM-AFM, not only in liquids but also in

60

ambient conditions since the hydration structures have also been observed in both the

61

environments.22,23

62

We define the water-restricting dimensions in the following statements. On the 0D surface

63

allowing zero tDOF, each water molecule near the surface is held in hollow sites in all lateral

64

directions (Fig. 1a). On the 1D surface allowing one tDOF, water molecules can move freely along

65

the groove structures but are relatively restricted along the transverse directions (Fig. 1b). On the

66

2D surface allowing two tDOF, water molecules can move relatively freely in all lateral directions

67

since the gaps between the surface protrusions are larger than water molecules (Fig. 1c). To discuss

68

variation in hydration structures introduced by the differences in the surface structure, we studied

69

three types of cleaved silicate surfaces having similar physical characteristics, albite (Alb,

70

NaAlSi3O8)10,24,25 in the tectosilicate group, which has two cleavage planes on (001) and (010), and

71

apophyllite-(KF) (Apo, KCa4Si8O20F·8H2O)26,27 in the phyllosilicate group. These surfaces allow

72

water molecules to have different tDOF because of the peculiar configurations of silicate

73

tetrahedrons (SiO4).

74

These minerals are also important in geoscience. Since Alb is classified in the feldspar group,

75

which is the most abundant in the earth's crust,25,28,29 the reactions with aqueous solutions

76

significantly influence the chemical composition of our environment. Apo is an important material / 31Environment ACS Paragon 4Plus

Page 4 of 31

Page 5 of 31 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

77

for the ion exchange process because it almost always occurs together with zeolites, especially in

78

traprock environments.27

79 80 81

METHODS

82

FM-AFM Setup

83

We used a customized commercial AFM head (Shimadzu: SPM-9600) with a home-built digital

84

PXI controller (National Instruments: NI PXI-8196) based on a high-speed field-programmable gate

85

array board (National Instruments: NI PXI-7833R) programmed by LabVIEW (National

86

Instruments) and a home-built FM detector circuit.30 To achieve quantitative and reproducible force

87

measurements in a liquid environment, we employed a photothermal excitation setup.31 We used a

88

rectangular cantilever with a gold backside coating (Nanosensors: PPP-NCHAuD), whose nominal

89

spring constant was 42 N/m. Those of the cantilevers used in the experiments for Alb (001), Alb

90

(010), and Apo were determined to be 38, 36, and 36 N/m by Sader’s method,32 respectively. The

91

resonance frequencies of the cantilevers were 127, 125, and 137 kHz in 100 mM KCl solutions,

92

respectively. Immediately prior to each experiment, organic contaminations on the tip were

93

removed by irradiating it using a UV-ozone cleaner (Filgen: UV253) for a few hours.

94

The measurement was performed in 100 mM potassium chloride aqueous solutions (KCl, 99.5%

95

purity, Wako Pure Chemical Industries, Ltd.) whose Debye length is 0.97 nm at 298 K. This reagent

96

was used without further purification and any pH regulation. The aqueous solution was slightly


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

97

acidified to a pH value of around 5.7 due to the dissolved CO2 gas. All the experiments are

98

conducted in a temperature-regulated enclosure (Mitsubishi Electric Engineering Company, Ltd.:

99

CN-40A), which can maintain a constant temperature of 298 ± 0.1 K and thus reduce the influence

100

of the thermal drift by the AFM head.

101 102

3D FM-AFM Measurement

103

More detailed procedure is described in our previous study.12 Acquired 3D ∆f map images of the

104

Alb (001), Alb (010), and Apo surfaces contain 6.97 × 6.80 × 1.35 nm3 (128 × 63 × 115 pixels),

105

5.81 × 8.00 × 1.35 nm3 (128 × 26 × 115 pixels), and 6.97 × 5.39 × 1.35 nm3 (128 × 93 × 115 pixels)

106

in XYZ, respectively. Each dataset was acquired by collecting 2D ZX ∆f map images with a tip

107

velocity of about 50–60 nm/s (40–50 Hz) of the ramp signal, and the total acquisition time for Alb

108

(001), Alb (010), and Apo were about 3.8, 1.5, and 4.2 minutes, respectively. The approach was

109

immediately stopped when the frequency shift signal reached a predetermined threshold value, then

110

the tip was retracted to the original position. We set the threshold value to be 1 kHz for all the

111

surfaces. The retraction curves were skipped and only the data of the approach curves were acquired

112

to reduce the image acquisition time. Because of our instrumental limitation, we did not increase the

113

approach speed over 100 nm/s, but we did not observe a significant dependency of the hydration

114

structures on the approach speed.

115 116

Post-processing of 3D FM-AFM Data / 31Environment ACS Paragon 6Plus

Page 6 of 31

Page 7 of 31 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

117

We established an automatic post-processing program that was developed in Visual Basic .NET

118

(Microsoft), which is essential for the efficient analysis of the large-size 3D map data. First, the 3D

119

∆f data were smoothed by using a spatial Gaussian filter with standard deviations of 0.045 nm (xy)

120

and 0.012 nm (z), and the 3D force data were obtained by converting each 2D ∆f map to a 2D force

121

map using Sader’s method.33 Since the background offset of the 1D curves in the 2D map contained

122

fluctuations, they were smoothed using a lateral line-by-line Gaussian filter with a standard

123

deviation of 1.23 nm before and after the conversion. Second, the resolution of the 3D data was

124

increased to 512 × 496 × 345, 512 × 701 × 345, and 512 × 393 × 345 pixels, respectively, for Alb

125

(001), Alb (010), and Apo using a Lanczos interpolation filter with a factor of 3 (Lanczos-3).34

126

Finally, the Y scales and X shear angles were adjusted by the drift correction such that the lattice

127

constants in the horizontal 2D maps match those in the literature (see Fig. S5 for the extent of the

128

filtering).35,36 For the vertical 2D force maps, the boundaries between the pixels with data (blue

129

regions) and without data (green regions) were interpolated using Lanczos-3.

130

For the creation of the Fourier-filtered images in Fig. 2, an automatic program was used to avoid

131

a biased image processing. Namely, after a fast Fourier transform (FFT) processing, all the

132

components lower than 2% of the maximum magnitude were set to zero in the frequency domain,

133

followed by an inverse FFT processing.

134 135

MD Simulations


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

136

We obtained the crystal structures of Alb and Apo from the American Mineralogist Crystal Structure

137

Database.35,36 We constructed (3 × 2), (3 × 3), and (3 × 3) crystal supercells which produced the

138

surface dimensions (relevant cell angles) of 2.44 × 2.56 nm2 (γ = 87.7°), 2.15 × 2.42 nm2 (γ = 64.2°),

139

and 2.70 × 2.70 nm2 (γ = 90.0°) for the Alb (001), Alb (010), and Apo surfaces, respectively (Fig.

140

S1). Thicknesses of the crystals were 2 unit cells for the Alb (001) and Alb (010) surfaces and 1 unit

141

cell for Apo. On the directions normal to the surfaces, we introduced water slabs approximately 3

142

nm thick, which contains 800–1000 water molecules. In line with earlier experimental10,29,37 and

143

theoretical38 studies, all the dangling (non-bridging) oxygens were terminated by hydrogens to form

144

the silanol/aluminol groups. For the Alb (001) and Alb (010) surfaces, counter sodium ions were

145

initially placed in the cavities of the tetrahedral groups to neutralize the surface negative charges.

146

The metal-OH angles and non-bonded parameters in hydroxyl group were set to approximately 122

147

degrees which was determined by ab initio calculation for the silanol group on silica.39

148

MD simulations were performed using Forcite (Dassault Systèmes BIOVIA)40 under constant

149

NVT conditions at 298K using a Nosé–Hoover scheme and a time step of 1 fs. Along all the

150

dimensions, periodic boundary conditions were employed. All the interactions (bonded and

151

non-bonded forces) between the atoms and electric charges were described by the CLAYFF force

152

field41 with the flexible SPC/E water model42 except for the silanol/aluminol groups. To maintain

153

the original crystal structures, all the atoms of the surfaces were treated as rigid using the RATTLE

154

algorithm.43 After water equilibration for 100 ps, the production MD runs were performed for


Page 8 of 31

Page 9 of 31 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

155

approximately 90 ns. The creations of the time-averaged maps and the computations of the water

156

self-diffusion coefficients were carried out from the consecutive trajectory files using a home-built

157

Perl conversion script and a Visual Basic .NET program. The zero-point distances were defined as

158

the average heights of the outermost oxygens at the bottom of the hollow sites on each surface. The

159

3D water density maps were created after smoothing the time-averaged 3D trajectory data using a

160

Gaussian kernel filter with a standard deviation of 0.037 nm.

161

All the cavities are occupied by the sodium ions for Alb (001), while only half the cavities are

162

occupied by the sodium ions for Alb (010). During the course of the simulation, any desorption of

163

the ions from the cavity sites was not observed. We confirmed that replacing the sodium ions by

164

potassium ions does not significantly change the conclusions.

165

*************************************************************************

166

RESULTS AND DISCUSSION

167

Definitions of Water-Restricting Dimensions

168

Figures 1d–f show the crystal structures of the cleaved Alb (001), Alb (010), and Apo surfaces,

169

respectively, all of which have negative charges being neutralized by adsorbed protons and cations

170

in a solution (Method section describes the details, and Movies S1 and S2 represent 3D crystal

171

structures). The adsorbed water molecules are restricted in hollow sites formed by the upward SiO4

172

tetrahedrons. Alb (001) has hollow sites having off-centered deeper cavities, all of which are

173

occupied by adsorbed cations one by one in solution (Fig. S2 shows detail schematics). This


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

174

anisotropy makes the surface symmetric line along the [100]38 indicated by the purple lines in Fig.

175

1d. Alb (010) has hollow sites each of which are continuously connected to neighboring sites, thus

176

forming a 1D groove-like structure along the [100] direction (the purple lines in Fig. 1e). Apo has

177

large square-arranged hollow sites, resembling a quasi-2D (Q-2D) structure in which water

178

molecules have two tDOF, shown in Fig. 1f, which makes the water self-diffusion coefficient (Dw)

179

larger than the other surfaces (Fig. S4). We refer to the Apo surface as Q-2D because its structure is

180

not a perfectly flat surface such as graphite.6 Although the 0D and 1D surfaces could also be

181

classified into the Q-2D surface, we distinguish them because each hollow site of the 0D and 1D

182

surfaces holds only single water molecule. In addition, tDOF of the Q-2D surface increases with

183

enlarging hollow size.

184

Our experiments were conducted in 100 mM KCl solutions for all the surfaces primarily because

185

it has been well tested for the high-resolution 3D FM-AFM measurements. Another technical reason

186

is that a high concentration of counter ion is required for the MD simulation to minimize the

187

simulation time and accurately handle the molecular behaviors. In Fig. 1g,h, atomically resolved

188

constant frequency shift (∆ƒ) images of Alb (001) and Alb (010) show clear dot-like

189

quasi-hexagonal lattice and zigzag stripe-like patterns,24 respectively; thus they reflect the

190

individual structural dimensions. The periodicities of the bright contrasts were 0.7−0.8 nm in both

191

the cases (marked by blue circles and zigzag lines). Meanwhile, the Apo surface showed a relatively

192

ambiguous atomically resolved image with a square lattice whose periodicity was 0.9 nm (see blue

193

circle in Fig.1i). Since these images were acquired with relatively small ∆f being comparable with / 31 ACS Paragon10 Plus Environment

Page 10 of 31

Page 11 of 31 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

194

the 2nd peak maxima, they do not represent the real surface but some of the higher hydration

195

structures (see the overlaid real surface structures in Figs. 1g–i).

196

*************************************************************************

197

3D Force Map Experiments and MD Simulations

198

Although the simple constant ∆f mode successfully revealed the dimensional difference, their

199

images may represent several hydration layers at the same time, thus preventing quantitative

200

discussion regarding tDOF. As such, we performed 3D force map measurements, which showed

201

atomically resolved complicated hydration structures in Fig. 2 (Movie S3). To validate these

202

experimental results, we simulated water density distributions using molecular dynamics (MD)

203

simulation. Several previous studies have often relied on the apparent similarities between the

204

observed force and simulated water density distributions.12,15-20,44 However, to realize more

205

quantitative comparisons, we converted them to force data using a solvent tip approximation

206

model.45 We defined the hydration layers as the 1stL, 1stH, and 2nd layers based on simulated force

207

profiles averaged laterally over the entire surfaces (as will be shown later in Figs. 4b,d,f). Note that

208

the 1stL and 1stH layers belong to the same peak but are observed as different subpeaks.

209 210

************************************************************************* Atomic-Resolution Hydration Layers

211

First, we compared the horizontal (constant height) force maps reconstructed near the apparent

212

surfaces, which were defined as contour planes of the threshold values and presumably reflect some

213

hydration layers. On the 0D and 1D surfaces, both the experimental/simulated results presented in / 31 ACS Paragon11 Plus Environment

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

214

Fig. 3a,b, show clear hexagonal-lattice dot-like atomically resolved images, but only the 1D surface

215

shows a slightly stripe-like contrast along the [001] direction, reflecting the tetrahedral

216

anisotropies.24 However, the Q-2D surface did not show such hexagonal-lattice in Fig. 3c but

217

dot-like square lattices with a relatively small periodicity of ~0.4 nm, implying that each of them

218

correspond to a single water molecule, because several water molecules can be held in each hollow

219

site (Fig. S2).

220

Meanwhile, in both the experimental/simulated results, the apparent innermost layers, which

221

were defined as the first hydration layers above the apparent surfaces, on the 0D and 1D surfaces in

222

Fig. 3d,e exhibit honeycomb-like and groove-like structures, respectively, which indicates that the

223

hydration structures reflect the expected tDOF. Concurrently, the result on the Q-2D surface

224

presented in Fig. 3f exhibit relatively ambiguous atomically resolved images having a square lattice

225

that repeats at intervals of 0.9 nm; thus reflecting the hollow structures that are much larger than the

226

water molecules. These results show that the apparent innermost layers (Fig. 3d,e,f) effectively

227

reflect the structural dimensions of the crystals whereas the apparent surfaces (Fig. 3a,b,c) always

228

appears with discrete dot-like structures for all the dimensions. Some adsorbates do appear on the

229

surfaces in Figs. 3b,c,e,f (marked with orange arrows), which are presumably organic contaminants

230

(Supplementary Note 4) and demonstrate the true atomic-resolution imaging.

231 232 233

************************************************************************* Comparison of Dot-Like Hydration Structures Second, we compared the vertical force maps which are reconstructed along the atomic rows / 31 ACS Paragon12 Plus Environment

Page 12 of 31

Page 13 of 31 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

234

indicated by the red broken lines in Fig. 3 and laterally averaged force profiles. We aligned the

235

profiles to match the vertical positions of the experimental/simulated peaks. On the 0D surface, both

236

the experimental/simulated results in Fig. 4a distinctly reveal elongated dot-like hydration structure

237

that are tilted slightly in the horizontal direction so that they reflect the surface anisotropy. MD

238

simulation revealed that these elongated broad hydration structures comprise continuous dots of the

239

1st–2nd layers. The averaged profiles in Fig. 4b showed the broad 1st peaks in both the

240

experiment/simulation, but the 2nd peak is barely seen in the experiment because the attractive

241

background force canceled it out. The range of the experimentally measured hydration interaction is

242

shorter than those measured by conventional nanomechanical tools because of an atomically

243

sharpened tip, which can avoid the influence of a macroscopic confinement effect.46,47 On the 1D

244

surface, as shown in Fig. 4c, along the 1D groove direction, the apparent surface exhibit

245

corrugations reflecting the 1stH hydration layers while the 2nd layers show laterally continuous

246

structures. Across the 1D groove direction, a checkerboard-like hydration structure appeared

247

(Supplementary Note 3). The averaged profiles in Fig. 4d show shoulder-like 1stH hydration peaks

248

in both the experiment/simulation. On the Q-2D surface, the experimental data in Fig. 4e show an

249

ambiguous arch-shaped 2nd hydration layer, whose feature was also reproduced in the simulated

250

data. In the averaged profiles shown in Figs. 4f, a fairly broad 3rd layer can be seen in both the

251

experimental/simulated results. However, the experimental 2nd layer shows a shoulder-like peak

252

whereas the simulated result shows an oscillatory peak. This inconsistency originates from not

253

considering the atoms other than the apex atom of the tip in the simulation, as elaborated later. Note / 31 ACS Paragon13 Plus Environment

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

254

that the force orders as well as the overall features show good agreement between the

255

experiments/simulations on all the surfaces despite its simple approximation, which validates these

256

analyses.

257 258

************************************************************************* Comparison of Hydration Forces

259

The experimental vertical maps presented in Fig. 4a,c,e suggest that the hydration structures

260

become ambiguous with increasing tDOF, but this tendency is not obvious in the simulations. To

261

understand this inconsistency, we compare their profiles in detail. For the magnitude of the

262

oscillatory force corresponding to the apparent innermost layers shown in Fig. 4b,d,f, the

263

experimental (simulated) values are gradually decreased with increasing tDOF, i.e., 76 (130), 35

264

(60), and 35 (44) pN for 0D, 1D, and Q-2D, respectively (marked with the green arrows). In the

265

solvation measurements in organic solvents, the solvation force decreases with the reducing

266

viscosity and increasing self-diffusion coefficient48. As we discussed in a previous study12, this

267

tendency seems to be true even in aqueous solutions because it is empirically considered that the

268

hydration structures are more easily observed in solutions than water, which can be explained by Dw

269

reduced by ions. In Fig. S4, Dw near the surface slightly increases with increasing tDOF, which

270

could be one cause of the weakening of the hydration force. However, this may not be the main

271

cause because the significant difference cannot been seen between the 0D and 1D structures (Figs.

272

S4a and S4c)

273

Since both the experimental/simulated results showed the same tendency, the above-mentioned / 31 ACS Paragon14 Plus Environment

Page 14 of 31

Page 15 of 31 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

274

inconsistency originates from different reason. Then, we noticed that the thicknesses of the

275

hydrations layers, which were not experimentally observed, become larger with increasing tDOF

276

(see the green boxes). From the water density profiles (Fig. S3d,h,l), these missing hydration

277

maxima are smaller than the bulk density, which means that they originate from the water molecules

278

embedded in the hollow sites. To observe these missing peaks, we further increased the threshold

279

value up to 1.6 kHz, but the tip change prevented the consecutive acquisition of the force curves,

280

implying that their experimental force maxima would be much larger than their simulated values.

281

This discrepancy is because, since the tip has a finite curvature radius, when the tip approaching, all

282

the tip apex atoms interact with the hydration layers and confines them to the hollow sites, which

283

produces the strong repulsive force. Namely, the thicknesses of the inaccessible hydration layers

284

reflect the hollow depths of the individual surfaces. With the increasing dimension, the thicknesses

285

of the inaccessible embedded hydration layers increase (Fig. 5), and consequently, the

286

experimentally observed hydration layer shifts to outer layer having lower Dw, which is the main

287

cause of hydration weakening. When the hollow size becomes sufficiently larger than the water size,

288

the embedded hydration layers would be measured.

289

Our findings provide guidance for prediction and analysis of the formation of hydration

290

structures on complicated biological molecules. Several preliminary experiments have shown the

291

hydration structures reflecting the secondary structures (i.e., alpha helices and beta sheets) of

292

proteins49,50 and nucleic acids51 rather than the small constituent units of the amino acid groups

293

(other investigations are in progress).

Our results have shown that the hydration structures on

/ 31 ACS Paragon15 Plus Environment

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

294

biological surfaces as well as inorganic surfaces can be predicted from the size and dimensions of

295

the molecular morphologies using the obtained knowledge and its analysis can be effectively

296

facilitated.

297

But we also noticed that their contrasts are much less pronounced than those in this study,

298

possibly because the periodicity of the molecular corrugation is much larger than the water size.

299

Therefore, for future applications to imaging such complicated structures, a method for enhancing

300

the hydration contrast is required, e.g., increasing the signal-to-ratio of the system,44 increasing the

301

electrolytic strength, and reducing the environmental temperature to suppress Dw and the molecular

302

fluctuations.

303

*************************************************************************

304

CONCLUSIONS

305

In this study, we systematically investigated the relationship between the formation of the

306

hydration structures and tDOF afforded to water molecules by surface structural dimensions via

307

ultra-low noise 3D FM-AFM experiments and MD simulations. For surface structures allowing zero,

308

one, and two tDOF, we prepared samples from cleaved silicate surfaces of Alb (001), Alb (010), and

309

Apo, respectively, which have different tetrahedral arrangements. We found that the apparent

310

innermost layers reflect the surface dimensions, i.e., honeycomb-like, groove-like, and ambiguous

311

square-lattice hydration structures, while the apparent surfaces always present laterally discrete

312

dot-like structures for all the dimensions. With increasing tDOF, Dw decreases and embedded

313

hydration layers increased, which leads to ambiguous hydration contrasts. These results / 31 ACS Paragon16 Plus Environment

Page 16 of 31

Page 17 of 31 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

314

demonstrate that the crystal structure’s restrictions on tDOF for water molecules significantly affect

315

vertical as well as horizontal hydration structures. These results will advance basic research in

316

determining the relationship between atomic-level biomolecular structures and biofunctions that are

317

mediated by local hydration structures.


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

318 319

Fig. 1 Structures of different lateral water-restricting dimensions. (a–c) Schematics of

320

the surface structures that restrict water molecules to 0D (a), 1D (b), and Q-2D (c). (d–f) Surface

321

crystal structures of albite (001) (d), albite (010) (e), and apophyllite (f) surfaces, which were

322

visualized by the crystallographic software VESTA.52 Yellow and green tetrahedrons indicate the

323

downward and upward tetrahedral silicates, respectively. (g–i) Drift-corrected atomically resolved

324

images of 0D (g), 1D (h), and Q-2D (i) surfaces acquired with constant frequency shift of 50−100

325

Hz, where the insets show the magnified images. Scale bars, 2 nm (g–i).

326 327


Page 18 of 31

Page 19 of 31 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

328 329

Fig. 2 Overview of 3D-FM-AFM results. (a–c) Representations of 3D-force map of 0D (a), 1D

330

(b), and Q-2D (c). The blue arrows indicate the vertical positions of the apparent innermost

331

hydration layers. The bottom faces show reconstructed constant frequency shift images of 50−100

332

Hz, which are obtained at the height where the blue arrows indicate. They correspond to the

333

contours of the 2nd–3rd hydration layer forces, which are almost the same height as those in Fig 1.

334 335 336 337


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

338

339 340

Fig. 3 Comparison of atomically resolved images. (a–f) Experimental (left panels) and

341

simulated (right panels) horizontal 2D force maps of the apparent surface (a–c) and apparent

342

innermost layer (d–f) layers, and top-view crystal structures (lower right panels) (d–f) of the 0D

343

(a,d), 1D (b,e), and Q-2D (c,f) surfaces. The insets enclosed by the purple lines show

344

Fourier-filtered images. The red, green, and orange broken lines show the positions at which the

345

vertical 2D force maps in Fig. 4, S5, and S6 were reconstructed, respectively. The orange arrows

346

indicate the organic adsorbate sites. In the crystal structures, green and yellow triangles indicate

347

upward and downward tetrahedral silicates, respectively. Scale bars, 1 nm (a–f).

348 349


Page 20 of 31

Page 21 of 31 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

350 351

Fig. 4 Comparison of dot-like hydration structures. (a–f) Experimental (left panels) and

352

simulated (right panels) vertical 2D force maps reconstructed along the red broken lines marked in

353

Fig. 3 (a,d,g); and experimental (upper panels) and simulated (lower panels) force profiles laterally

354

averaged over the whole surfaces at 40 randomly selected pixels (c,f,i) of the 0D (a–d), 1D (e–h),

355

and Q-2D (i–I) surfaces. In the 2D maps in (a,d,g), the force maxima enclosed by the red broken

356

curves indicate the characteristic shapes of the hydration structures, i.e., dots, lines, and arches.

357

Note that density peaks are shifted to further away from the surface by approximately quarter of the

358

diameter of the water molecule than the force peaks, but the main contrast features are not changed.

359

In the force profiles, the green boxes show the inaccessible hydration regions. Scale bars, 0.3 nm

360

(a,d,g).

361


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

362 363

364 365

Fig. 5 Schematics of hydration structure dependence on surface structure. (a,b)

366

Hydration structures formed on surfaces with small (a) and large (b) dimension (or periodicities)

367

compared to the diameter of the water molecule. The real surface indicates the positions of the

368

centers of the outermost oxygens.

369 370 371


Page 22 of 31

Page 23 of 31 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

372 373 374 375 376

ASSOCIATED CONTENT

377 378

Supporting Information

379

Figure S1: Snapshots from the MD simulations; Figure S2: Schematics of hydration layers; Figure

380

S3: Simulated water densities; Figure S4: Water self-diffusion coefficients; Figure S5: Comparison

381

of 3D data before/after filtering; Figure S6: Photographs of phyllosilicate minerals; Figure S7: XPS

382

spectra of albite; Figure S8: XPS spectra of apophyllite; Figure S9: Topographic images of cleaved

383

samples; Figure S10: Comparison of dot-like hydration structures along green lines; Figure S11:

384

Cross-sectional force map on an adsorbate; Table S1: Analysis of XPS spectra; Movie S1: Crystal

385

structures of albite surfaces; Movie S2: Crystal structure of apophyllite surface; Movie S3: Full

386

3D-force map result obtained by 3D FM-AFM.

387 388 389 390

Conflicts of interest

391

There are no conflicts of interest to declare.

392 393 394 395

Acknowledgements

396

This work was supported by KAKENHI, Japan Society for the Promotion of Science (Grant No.

397

24221008, 25286057, 15K17467, and 16J01165); Foundation Advanced Technology Institute; the

398

Murata Science Foundation; and Nanotech Career-up Alliance. The computer resources for the MD

399

simulation were provided by SuperComputer System, Institute for Chemical Research, Kyoto

400

University.

401 402 / 31 ACS Paragon23 Plus Environment

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

403 404

References

405 406

(1)

407 408

electrochemical interfaces. Nat. Mater. 2017, 16, 57-69. (2)

409 410

Stamenkovic, V. R.; Strmcnik, D.; Lopes, P. P.; Markovic, N. M. Energy and fuels from

Lukatskaya, M. R.; Dunn, B.; Gogotsi, Y. Multidimensional materials and device architectures for future hybrid energy storage. Nat. Commun. 2016, 7, 12647.

(3)

Hussain, H.; Tocci, G.; Woolcot, T.; Torrelles, X.; Pang, C. L.; Humphrey, D. S.; Yim, C.

411

M.; Grinter, D. C.; Cabailh, G.; Bikondoa, O.; Lindsay, R.; Zegenhagen, J.; Michaelides, A.;

412

Thornton, G. Structure of a model TiO2 photocatalytic interface. Nat. Mater. 2017, 16,

413

461-466.

414

(4)

415 416

Green, J. J.; Elisseeff, J. H. Mimicking biological functionality with polymers for biomedical applications. Nature 2016, 540, 386-394.

(5)

Kuna, J. J.; Voitchovsky, K.; Singh, C.; Jiang, H.; Mwenifumbo, S.; Ghorai, P. K.; Stevens,

417

M. M.; Glotzer, S. C.; Stellacci, F. The effect of nanometre-scale structure on interfacial

418

energy. Nat. Mater. 2009, 8, 837-842.

419

(6)

420 421 422

Naydenov, B.; Boland, J. J. Engineering the electronic structure of surface dangling bond nanowires of different size and dimensionality. Nanotechnology 2013, 24, 275202.

(7)

Lafferentz, L.; Eberhardt, V.; Dri, C.; Africh, C.; Comelli, G.; Esch, F.; Hecht, S.; Grill, L. Controlling on-surface polymerization by hierarchical and substrate-directed growth. Nat.


Page 24 of 31

Page 25 of 31 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

423 424

Chem. 2012, 4, 215-220. (8)

425 426

Nanotechnol. 2010, 5, 477-479. (9)

427 428

(10)

Fenter, P.; Sturchio, N. C. Mineral–water interfacial structures revealed by synchrotron X-ray scattering. Prog. Surf. Sci. 2004, 77, 171-258.

(11)

431 432

Jariwala, D.; Marks, T. J.; Hersam, M. C. Mixed-dimensional van der Waals heterostructures. Nat. Mater. 2017, 16, 170-181.

429 430

Manoharan, H. C. TOPOLOGICAL INSULATORS A romance with many dimensions. Nat.

Daillant, J.; Gibaud, A. 2009 X-ray and Neutron Reflectivity: Principles and Applications: (Springer: Berlin, Germany)

(12)

Umeda, K.; Zivanovic, L.; Kobayashi, K.; Ritala, J.; Kominami, H.; Spijker, P.; Foster, A.

433

S.; Yamada, H. Atomic-resolution three dimensional hydration structures on a

434

heterogeneously charged surface. Nat. Commun. 2017, 8, 2111.

435

(13)

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

436

Molecules at the Mica-Water Interface Visualized by Three-Dimensional Scanning Force

437

Microscopy. Phys. Rev. Lett. 2010, 104, 016101.

438

(14)

439 440

Labuda, A.; Kobayashi, K.; Suzuki, K.; Yamada, H.; Grütter, P. Monotonic Damping in Nanoscopic Hydration Experiments. Phys. Rev. Lett. 2013, 110, 066102.

(15)

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

441

M.; Yamada, H. Visualization of hydration layers on muscovite mica in aqueous solution by

442

frequency-modulation atomic force microscopy. J. Chem. Phys. 2013, 138, 184704. / 31 ACS Paragon25 Plus Environment

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

443

(16)

Miyazawa, K.; Kobayashi, N.; Watkins, M.; Shluger, A. L.; Amano, K.; Fukuma, T. A

444

relationship between three-dimensional surface hydration structures and force distribution

445

measured by atomic force microscopy. Nanoscale 2016, 8, 7334-7342.

446

(17)

Söngen, H.; Marutschke, C.; Spijker, P.; Holmgren, E.; Hermes, I.; Bechstein, R.; Klassen,

447

S.; Tracey, J.; Foster, A. S.; Kühnle, A. Chemical Identification at the Solid−Liquid Interface.

448

Langmuir 2017, 33, 125-129.

449

(18)

Ito, F.; Kobayashi, K.; Spijker, P.; Zivanovic, L.; Umeda, K.; Nurmi, T.; Holmberg, N.;

450

Laasonen, K.; Foster, A. S.; Yamada, H. Molecular Resolution of the Water Interface at an

451

Alkali Halide with Terraces and Steps. J. Phys. Chem. C 2016, 120, 19714-19722.

452

(19)

Martin-Jimenez, D.; Chacon, E.; Tarazona, P.; Garcia, R. Atomically resolved

453

three-dimensional structures of electrolyte aqueous solutions near a solid surface. Nat.

454

Commun. 2016, 7, 12164.

455

(20)

Fukuma, T.; Reischl, B.; Kobayashi, N.; Spijker, P.; Canova, F. F.; Miyazawa, K.; Foster, A.

456

S. Mechanism of atomic force microscopy imaging of three-dimensional hydration

457

structures at a solid-liquid interface. Phys. Rev. B 2015, 92, 155412.

458

(21)

Umeda, K.; Kobayashi, K.; Oyabu, N.; Matsushige, K.; Yamada, H. Molecular-scale

459

quantitative charge density measurement of biological molecule by frequency modulation

460

atomic force microscopy in aqueous solutions. Nanotechnology 2015, 26, 285103.

461 462

(22)

Wastl, D. S.; Judmann, M.; Weymouth, A. J.; Giessibl, F. J. Atomic Resolution of Calcium and Oxygen Sub lattices of Calcite in Ambient Conditions by Atomic Force Microscopy / 31 ACS Paragon26 Plus Environment

Page 26 of 31

Page 27 of 31 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

463 464

Using qPlus Sensors with Sapphire Tips. ACS Nano 2015, 9, 3858-3865. (23)

465 466

mica under a thin water film grown from humid air. Sci. Rep. 2017, 7, 4054. (24)

467 468

Arai, T.; Sato, K.; Iida, A.; Tomitori, M. Quasi-stabilized hydration layers on muscovite

Drake, B.; Hellmann, R. Atomic Force Microscopy Imaging of the Albite (010) Surface. Am. Mineral. 1991, 76, 1773-1776.

(25)

Jordan, G.; Higgins, S. R.; Eggleston, C. M.; Swapp, S. M.; Janney, D. E.; Knauss, K. G.

469

Acidic dissolution of plagioclase: In-situ observations by hydrothermal atomic force

470

microscopy. Geochim. Cosmochim. Acta 1999, 63, 3183-3191.

471

(26)

Henderson, G. S.; Vrdoljak, G. A.; Eby, R. K.; Wicks, F. J.; Rachlin, A. L. Atomic-Force

472

Microscopy Studies of Layer Silicate Minerals. Colloids Surf. A: Physicochem. Eng. Aspects

473

1994, 87, 197-212.

474

(27)

Aldushin, K.; Jordan, G.; Rammensee, W.; Schmahl, W. W.; Becker, H. W. Apophyllite

475

(001) surface alteration in aqueous solutions studied by HAFM. Geochim. Cosmochim. Acta

476

2004, 68, 217-226.

477

(28)

Fenter, P.; Teng, H.; Geissbuhler, P.; Hanchar, J. M.; Nagy, K. L.; Sturchio, N. C.

478

Atomic-scale

structure

of

the

orthoclase

(001)-water

interface

measured

479

high-resolution X-ray reflectivity. Geochim. Cosmochim. Acta 2000, 64, 3663-3673.

with

480

(29)

Parsons, I. 1994 Feldspars and their Reactions: (Springer: Berlin, Germany)

481

(30)

Kobayashi, K.; Yamada, H.; Itoh, H.; Horiuchi, T.; Matsushige, K. Analog frequency

482

modulation detector for dynamic force microscopy. Rev. Sci. Instrum. 2001, 72, 4383-4387. / 31 ACS Paragon27 Plus Environment

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

483

(31)

Kobayashi, K.; Yamada, H.; Matsushige, K. Reduction of frequency noise and frequency

484

shift by phase shifting elements in frequency modulation atomic force microscopy. Rev. Sci.

485

Instrum. 2011, 82, 033702.

486

(32)

487 488

microscope cantilevers. Rev. Sci. Instrum. 1999, 70, 3967-3969. (33)

489 490

(34)

Burger, W.; Burge, M. J. 2009 Principles of digital image processing: core algorithms: (Springer: Berlin, Germany)

(35)

493 494

Sader, J. E.; Jarvis, S. P. Accurate formulas for interaction force and energy in frequency modulation force spectroscopy. Appl. Phys. Lett. 2004, 84, 1801-1803.

491 492

Sader, J. E.; Chon, J. W. M.; Mulvaney, P. Calibration of rectangular atomic force

Harlow, G. E.; Brown, G. E. Low Albite - an X-Ray and Neutron-Diffraction Study. Am. Mineral. 1980, 65, 986-995.

(36)

Chao, G. Y. REFINEMENT OF THE CRYSTAL STRUCTURE OF APOPHYLLITE II.

495

DETERMINATION OF HYDROGEN POSITIONS BY X-RAY DIFFRACTION. Am.

496

Mineral. 1971, 56, 1234-1242.

497

(37)

Fenter, P.; Cheng, L.; Park, C.; Zhang, Z.; Sturchio, N. C. Structure of the orthoclase (001)-

498

and (010)-water interfaces by high-resolution X-ray reflectivity. Geochim. Cosmochim. Acta

499

2003, 67, 4267-4275.

500

(38)

501 502

Kerisit, S.; Liu, C. X.; Ilton, E. S. Molecular dynamics simulations of the orthoclase (001)and (010)-water interfaces. Geochim. Cosmochim. Acta 2008, 72, 1481-1497.

(39)

Saengsawang, O.; Remsungnen, T.; Fritzsche, S.; Haberlandt, R.; Hannongbua, S. Structure / 31 ACS Paragon28 Plus Environment

Page 28 of 31

Page 29 of 31 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

503

and energetics of water−silanol binding on the surface of silicalite-1: Quantum chemical

504

calculations. J. Phys. Chem. B 2005, 109, 5684-5690.

505

(40)

Forcite BIOVIA Materials Stuido 2016 ed.: (Accelrys - Dassault Systèmes, San Diego, CA)

506

(41)

Cygan, R. T.; Liang, J. J.; Kalinichev, A. G. Molecular models of hydroxide, oxyhydroxide,

507

and clay phases and the development of a general force field. J. Phys. Chem. B 2004, 108,

508

1255-1266.

509

(42)

510 511

Potentials. J. Phys. Chem. 1987, 91, 6269-6271. (43)

512 513

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

Andersen, H. C. Rattle: A “velocity” version of the shake algorithm for molecular dynamics calculations. J. Comp. Phys. 1983, 52, 24-34.

(44)

Miyata, K.; Tracey, J.; Miyazawa, K.; Haapasilta, V.; Spijker, P.; Kawagoe, Y.; Foster, A. S.;

514

Tsukamoto, K.; Fukuma, T. Dissolution Processes at Step Edges of Calcite in Water

515

Investigated by High-Speed Frequency Modulation Atomic Force Microscopy and

516

Simulation. Nano Lett. 2017, 17, 4083-4089.

517

(45)

518 519

Watkins, M.; Reischl, B. A simple approximation for forces exerted on an AFM tip in liquid. J. Chem. Phys. 2013, 138, 154703.

(46)

Kaggwa, G. B.; Nalam, P. C.; Kilpatrick, J. I.; Spencer, N. D.; Jarvis, S. P. Impact of

520

Hydrophilic/Hydrophobic Surface Chemistry on Hydration Forces in the Absence of

521

Confinement. Langmuir 2012, 28, 6589-6594.

522

(47)

Kilpatrick, J. I.; Loh, S. H.; Jarvis, S. P. Directly Probing the Effects of Ions on Hydration / 31 ACS Paragon29 Plus Environment

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

523 524

Forces at Interfaces. J. Am. Chem. Soc. 2013, 135, 2628-2634. (48)

Cui, T.; Lahiri, A.; Carstens, T.; Borisenko, N.; Pulletikurthi, G.; Kuhl, C.; Endres, F.

525

Influence of Water on the Electrified Ionic Liquid/Solid Interface: A Direct Observation of

526

the Transition from a Multilayered Structure to a Double-Layer Structure. J. Phys. Chem. C

527

2016, 120, 9341-9349.

528

(49)

Herruzo, E. T.; Asakawa, H.; Fukuma, T.; Garcia, R. Three-dimensional quantitative force

529

maps in liquid with 10 piconewton, angstrom and sub-minute resolutions. Nanoscale 2013,

530

5, 2678-2685.

531

(50)

532 533

Kimura, K.; Ido, S.; Oyabu, N.; Kobayashi, K.; Hirata, Y.; Imai, T.; Yamada, H. Visualizing water molecule distribution by atomic force microscopy. J. Chem. Phys. 2010, 132, 194705.

(51)

Ido, S.; Kimura, K.; Oyabu, N.; Kobayashi, K.; Tsukada, M.; Matsushige, K.; Yamada, H.

534

Beyond the Helix Pitch: Direct Visualization of Native DNA in Aqueous Solution. ACS

535

Nano 2013, 7, 1817-1822.

536 537

(52)

Momma, K.; Izumi, F. VESTA 3 for three-dimensional visualization of crystal, volumetric and morphology data. J. Appl. Crystallogr. 2011, 44, 1272-1276.

538 539


Page 30 of 31

Page 31 of 31 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

540 541

Table of Contents (TOC)

542

543 544 545 546 547


Atomic-Scale 3D Local Hydration Structures Influenced by Water

Recommend Documents