| 76 |
|
another\cite{Casassa91, Sukhorukov13, Pritchard12, Lishman13} or the shearing |
| 77 |
|
of ice through water\cite{Cuffey99, Bell08}. Using molecular dynamics |
| 78 |
|
simulations, Samadashvili has recently shown that when two smooth ice slabs |
| 79 |
< |
slide past one another, a stable liquid-like layer develops between them.To |
| 80 |
< |
fundamentally understand these processes an understanding of the ice/water |
| 81 |
< |
interfaces is needed. |
| 79 |
> |
slide past one another, a stable liquid-like layer develops between |
| 80 |
> |
them\cite{Samadashvili13}. To fundamentally understand these processes, a |
| 81 |
> |
molecular understanding of the ice/water interfaces is needed. |
| 82 |
|
|
| 83 |
|
Investigation of the ice/water interface is also crucial in understanding |
| 84 |
< |
the fundamental processes of nucleation, crystal |
| 84 |
> |
processes such as nucleation, crystal |
| 85 |
|
growth,\cite{Han92, Granasy95, Vanfleet95} and crystal |
| 86 |
|
melting\cite{Weber83, Han92, Sakai96, Sakai96B}. Insight gained to these |
| 87 |
|
properties can also be applied to biological systems of interest, such as |
| 97 |
|
systems. There has been extensive work parameterizing models for liquid water, |
| 98 |
|
such as the SPC\cite{Berendsen81}, SPC/E\cite{Berendsen87}, |
| 99 |
|
TIP4P\cite{Jorgensen85}, TIP4P/2005\cite{Abascal05}, |
| 100 |
< |
($\dots$), and more recently to improve these models for simulating |
| 100 |
> |
($\dots$), and more recently, models for simulating |
| 101 |
|
the solid phases of water, such as the TIP4P/Ice\cite{Abascal05b} model. The |
| 102 |
|
melting point of various crystal structures of ice have been calculated for |
| 103 |
|
many of these models |
| 104 |
|
(SPC\cite{Karim90,Abascal07}, SPC/E\cite{Baez95,Arbuckle02,Gay02,Bryk02,Bryk04b,Sanz04b,Gernandez06,Abascal07,Vrbka07}, TIP4P\cite{Karim88,Gao00,Sanz04,Sanz04b,Koyama04,Wang05,Fernandez06,Abascal07}, TIP5P\cite{Sanz04,Koyama04,Wang05,Fernandez06,Abascal07}), |
| 105 |
|
and the partial or complete phase diagram for the model has been determined |
| 106 |
< |
(SPC/E\cite{Baeaz95,Bryk04b,Sanz04b}, TIP4P\cite{Sanz04,Sanz04b,Koyama04}, TIP5P\cite{Sanz04,Koyama04}). |
| 107 |
< |
Knowing the melting point for these models has allowed for the investigation |
| 108 |
< |
of ice/water interfaces. |
| 106 |
> |
(SPC/E\cite{Baez95,Bryk04b,Sanz04b}, TIP4P\cite{Sanz04,Sanz04b,Koyama04}, TIP5P\cite{Sanz04,Koyama04}). |
| 107 |
> |
Knowing the behavior and melting point for these models has enabled an initial |
| 108 |
> |
investigation of ice/water interfaces. |
| 109 |
|
|
| 110 |
|
The Ice-I$_\mathrm{h}$/water quiescent interface has been extensively studied |
| 111 |
|
over the past 30 years by theory and experiment. Haymet \emph{et al.} have |
| 115 |
|
recent years, Haymet has focused on investigating the effects cations and |
| 116 |
|
anions have on crystal nucleaion and |
| 117 |
|
melting.\cite{Bryk04,Smith05,Wilson08,Wilson10} Nada and Furukawa have studied |
| 118 |
< |
the the basal- and prismatic-water interface width\cite{Nada95}, surface |
| 119 |
< |
restructuring at temperatures approaching the melting point\cite{Nada00}, |
| 120 |
< |
and the mechanism of ice growth inhibition by antifreeze |
| 118 |
> |
the the basal- and prismatic-water interface width\cite{Nada95}, crystal |
| 119 |
> |
surface restructuring at temperatures approaching the melting |
| 120 |
> |
point\cite{Nada00}, and the mechanism of ice growth inhibition by antifreeze |
| 121 |
|
proteins\cite{Nada08,Nada11,Nada12}. Nada has developed a six-site water model |
| 122 |
|
for ice/water interfaces near the melting point\cite{Nada03}, and studied the |
| 123 |
|
dependence of crystal growth shape on applied pressure\cite{Nada11b}. Using |
| 124 |
|
this model, Nada and Furukawa have established differential |
| 125 |
|
growth rates for the basal, prismatic, and secondary prismatic facets of |
| 126 |
< |
Ice-I$_\mathrm{h}$ and found they were due to a reordering of the hydrogen |
| 126 |
> |
Ice-I$_\mathrm{h}$ and found their origins due to a reordering of the hydrogen |
| 127 |
|
bond network in water near the interface\cite{Nada05}. While the work |
| 128 |
|
described so far has mainly focused on bulk water on ice, there is significant |
| 129 |
|
interest in thin films of water on ice surfaces as well. |
| 190 |
|
instead of 225K. The ice / water systems generated were then equilibrated |
| 191 |
|
to 225K. The resulting pyramidal system was |
| 192 |
|
$37.47 \times 29.50 \times 93.02$ \AA\ with 1216 |
| 193 |
< |
SPC/E\cite{Berendsen97} molecules in the ice slab, and 2203 in the liquid |
| 193 |
> |
SPC/E\cite{Berendsen87} molecules in the ice slab, and 2203 in the liquid |
| 194 |
|
phase. The secondary |
| 195 |
|
prismatic system generated was $71.87 \times 31.66 \times 161.55$ \AA\ with |
| 196 |
|
3840 |
| 234 |
|
local tetrahedral order parameter to quantify the width of the interface, |
| 235 |
|
which was originally described by Kumar\cite{Kumar09} and |
| 236 |
|
Errington\cite{Errington01}, and used by Bryk and Haymet in a previous study |
| 237 |
< |
of ice/water interfaces.\cite{Bryk2004b} |
| 237 |
> |
of ice/water interfaces.\cite{Bryk04b} |
| 238 |
|
|
| 239 |
|
The local tetrahedral order parameter, $q(z)$, is given by |
| 240 |
|
\begin{equation} |
| 266 |
|
bulk to ice |
| 267 |
|
transition, while accounting for the thermal influence on the profile by the |
| 268 |
|
kinetic energy exchanges of the VSS-RNEMD moves. In panels $b$ and $c$, the |
| 269 |
< |
resulting thermal and velocity gradients from the imposed kinetic energy and |
| 269 |
> |
resulting thermal and velocity gradients from an imposed kinetic energy and |
| 270 |
|
momentum fluxes can be seen. The verticle dotted |
| 271 |
|
lines traversing all three panels indicate the midpoints of the interface |
| 272 |
|
as determined by the hyperbolic tangent fit of the tetrahedrality profiles. |
| 273 |
|
|
| 274 |
|
From fitting the tetrahedrality profiles for each of the 0.5 nanosecond |
| 275 |
< |
simulations (panel c of Figures \ref{fig:spComic} and \ref{fig:pyrComic}) |
| 276 |
< |
by Eq. 6\cite{Louden13},we find the interfacial width to be |
| 275 |
> |
simulations (panel c of Figures \ref{fig:pyrComic} and \ref{fig:spComic}) |
| 276 |
> |
by eq. 6\cite{Louden13},we find the interfacial width to be |
| 277 |
|
3.2 $\pm$ 0.2 and 3.2 $\pm$ 0.2 \AA\ for the control system with no applied |
| 278 |
|
momentum flux for both the pyramidal and secondary prismatic systems. |
| 279 |
|
Over the range of shear rates investigated, |
| 312 |
|
|
| 313 |
|
To investigate the dynamics of the water molecules across the interface, the |
| 314 |
|
systems were divided in the $z$-dimension into bins, each $\approx$ 3 \AA\ |
| 315 |
< |
wide, and \eqref{C(t)1} was computed for each of the bins. A water |
| 315 |
> |
wide, and eq. \eqref{C(t)1} was computed for each of the bins. A water |
| 316 |
|
molecule was allocated to a particular bin if it was initially in the bin |
| 317 |
< |
at time zero. To compute \eqref{C(t)1}, each 0.5 ns simulation was followed |
| 318 |
< |
by an additional 200 ps NVE simulation during which the |
| 317 |
> |
at time zero. To compute eq. \eqref{C(t)1}, each 0.5 ns simulation was |
| 318 |
> |
followed by an additional 200 ps NVE simulation during which the |
| 319 |
|
position and orientations of each molecule were recorded every 0.1 ps. |
| 320 |
|
|
| 321 |
|
The data obtained for each bin was then fit to a triexponential decay given by |
| 377 |
|
on the temperature of the liquid water in the system. We believe this |
| 378 |
|
dependence |
| 379 |
|
arrises from the sharp discontinuity of the viscosity for the SPC/E model |
| 380 |
< |
at temperatures approaching 200 K\cite{kuang12}. Due to this, we propose |
| 380 |
> |
at temperatures approaching 200 K\cite{Kuang12}. Due to this, we propose |
| 381 |
|
a weighting to the interfacial friction coefficient, $\kappa$ by the |
| 382 |
|
shear viscosity of the fluid at 225 K. The interfacial friction coefficient |
| 383 |
|
relates the shear stress with the relative velocity of the fluid normal to the |
| 413 |
|
length. The VSS were attempted every timestep, which was set to 2 fs. |
| 414 |
|
For our SPC/E systems, we found $\eta(225)$ to be 0.0148 $\pm$ 0.0007 Pa s, |
| 415 |
|
roughly ten times larger than the value found for 280 K SPC/E bulk water by |
| 416 |
< |
Kuang\cite{kuang12}. |
| 416 |
> |
Kuang\cite{Kuang12}. |
| 417 |
|
|
| 418 |
|
The interfacial friction coefficient, $\kappa$, can equivalently be expressed |
| 419 |
|
as the ratio of the viscosity of the fluid to the slip length, $\delta$, which |
| 430 |
|
'slipperiness' of the interface can be taken as an indication of how |
| 431 |
|
hydrophobic or hydrophilic the interface is. The calculated $\kappa$ values |
| 432 |
|
found for the four crystal facets of Ice-I$_\mathrm{h}$ investigated are shown |
| 433 |
< |
in Table \ref{tab:kapa}. The basal and pyramidal facets were found to have |
| 433 |
> |
in Table \ref{tab:kappa}. The basal and pyramidal facets were found to have |
| 434 |
|
similar values of $\kappa \approx$ 0.0006 |
| 435 |
|
(amu \AA\textsuperscript{-2} fs\textsuperscript{-1}), while values of |
| 436 |
|
$\kappa \approx$ 0.0003 (amu \AA\textsuperscript{-2} fs\textsuperscript{-1}) |
| 437 |
|
were found for the prismatic and secondary prismatic systems. |
| 438 |
|
These results indicate that the basal and pyramidal facets are |
| 439 |
|
more hydrophilic than the prismatic and secondary prismatic facets. |
| 440 |
– |
%This indicates something about the similarity between the two facets that |
| 441 |
– |
%share similar values... |
| 442 |
– |
%Maybe find values for kappa for other materials to compare against? |
| 440 |
|
|
| 441 |
< |
%\begin{table}[h] |
| 442 |
< |
%\centering |
| 443 |
< |
%\caption{$\kappa$ values for the basal, prismatic, pyramidal, and secondary \ |
| 444 |
< |
%prismatic facets of Ice-I$_\mathrm{h}$} |
| 445 |
< |
%\label{tab:kappa} |
| 446 |
< |
%\begin{tabular}{|ccc|} \hline |
| 447 |
< |
% & \multicolumn{2}{c|}{$\kappa_{Drag direction}$ (amu \AA\textsuperscript{-2} fs\textsuperscript{-1})} \\ |
| 448 |
< |
% Interface & $\kappa_{x}$ & $\kappa_{y}$ \\ \hline |
| 449 |
< |
% basal & $0.00059 \pm 0.00003$ & $0.00065 \pm 0.00008$ \\ |
| 450 |
< |
% prismatic & $0.00030 \pm 0.00002$ & $0.00030 \pm 0.00001$ \\ |
| 451 |
< |
% pyramidal & $0.00058 \pm 0.00004$ & $0.00061 \pm 0.00005$ \\ |
| 452 |
< |
% secondary prismatic & $0.00035 \pm 0.00001$ & $0.00033 \pm 0.00002$ \\ \hline |
| 453 |
< |
%\end{tabular} |
| 454 |
< |
%\end{table} |
| 441 |
> |
\subsection{Dynamic water contact angle} |
| 442 |
> |
The hydrophobicity or hydrophilicity of a surface can be described by the |
| 443 |
> |
extent a droplet of water wets the surface. The contact angle formed between |
| 444 |
> |
the solid and the liquid, $\theta$, which relates the free energies of the |
| 445 |
> |
three interfaces involved, is given by Young's equation. |
| 446 |
> |
\begin{equation}\label{young} |
| 447 |
> |
\cos\theta = (\gamma_{sv} - \gamma_{sl})/\gamma_{lv} |
| 448 |
> |
\end{equation} |
| 449 |
> |
Here $\gamma_{sv}$, $\gamma_{sl}$, and $\gamma_{lv}$ are the free energies |
| 450 |
> |
of the solid/vapor, solid/liquid, and liquid/vapor interfaces respectively. |
| 451 |
> |
Large contact angles ($\theta$ $\gg$ 90\textsuperscript{o}) correspond to low |
| 452 |
> |
wettability and hydrophobic surfaces, while small contact angles |
| 453 |
> |
($\theta$ $\ll$ 90\textsuperscript{o}) correspond to high wettability and |
| 454 |
> |
hydrophilic surfaces. Experimentally, measurements of the contact angle |
| 455 |
> |
of sessile drops has been used to quantify the extent of wetting on surfaces |
| 456 |
> |
with thermally selective wetting charactaristics\cite{Tadanaga00,Liu04,Sun04}, |
| 457 |
> |
as well as nano-pillared surfaces with electrically tunable Cassie-Baxter and |
| 458 |
> |
Wenzel states\cite{Herbertson06,Dhindsa06,Verplanck07,Ahuja08,Manukyan11}. |
| 459 |
> |
Luzar and coworkers have done significant work modeling these transitions on |
| 460 |
> |
nano-patterned surfaces\cite{Daub07,Daub10,Daub11,Ritchie12}, and have found |
| 461 |
> |
the change in contact angle to be due to the external field perturbing the |
| 462 |
> |
hydrogen bonding of the liquid/vapor interface\cite{Daub07}. |
| 463 |
|
|
| 464 |
+ |
Here, we will calculate the contact angle of a water droplet as it spreads |
| 465 |
+ |
across each of the four ice I$_\mathrm{h}$ crystal facets in order to |
| 466 |
+ |
determine the surface's relative hydrophilicites. The ice surfaces were |
| 467 |
+ |
oriented so that the desired facet was exposed to the positive z dimension. |
| 468 |
+ |
The sizes and number of molecules in each of the surfaces is given in Table |
| 469 |
+ |
\ref{tab:ice_sheets}. Molecular restraints were applied to the center of mass |
| 470 |
+ |
of the rigid bodies to prevent surface melting, however the molecules were |
| 471 |
+ |
allowed to reorient themselves freely. The water doplet to be placed on the |
| 472 |
+ |
surface contained 2048 SPC/E molecules, which has been found to produce |
| 473 |
+ |
agreement for the Young contact angle extrapolated to an infinite drop |
| 474 |
+ |
size\cite{Daub10}. The surfaces and droplet were equilibrated to 225 K, at |
| 475 |
+ |
which time the droplet was placed 3-5 \AA\ above the surface at 5 unique |
| 476 |
+ |
locations. Each simulation was 5 ns in length and conducted in the NVE |
| 477 |
+ |
ensemble. |
| 478 |
|
|
| 479 |
|
|
| 480 |
|
|
| 481 |
+ |
|
| 482 |
|
\begin{table}[h] |
| 483 |
|
\centering |
| 484 |
|
\caption{Phyiscal properties of the basal, prismatic, pyramidal, and secondary prismatic facets of Ice-I$_\mathrm{h}$} |
| 493 |
|
\end{tabular} |
| 494 |
|
\end{table} |
| 495 |
|
|
| 476 |
– |
|
| 477 |
– |
%\begin{table}[h] |
| 478 |
– |
%\centering |
| 479 |
– |
%\caption{Solid-liquid friction coefficients (measured in amu~fs\textsuperscript\ |
| 480 |
– |
%{-1}). \\ |
| 481 |
– |
%\textsuperscript{a} See ref. \onlinecite{Louden13}. } |
| 482 |
– |
%\label{tab:lambda} |
| 483 |
– |
%\begin{tabular}{|ccc|} \hline |
| 484 |
– |
% & \multicolumn{2}{c|}{Drag direction} \\ |
| 485 |
– |
% Interface & $x$ & $y$ \\ \hline |
| 486 |
– |
% basal\textsuperscript{a} & $0.08 \pm 0.02$ & $0.09 \pm 0.03$ \\ |
| 487 |
– |
% prismatic (T = 225)\textsuperscript{a} & $0.037 \pm 0.008$ & $0.04 \pm 0.01$ \\ |
| 488 |
– |
% prismatic (T = 230) & $0.10 \pm 0.01$ & $0.070 \pm 0.006$\\ |
| 489 |
– |
% pyramidal & $0.13 \pm 0.03$ & $0.14 \pm 0.03$ \\ |
| 490 |
– |
% secondary prismatic & $0.13 \pm 0.02$ & $0.12 \pm 0.03$ \\ \hline |
| 491 |
– |
%\end{tabular} |
| 492 |
– |
%\end{table} |
| 496 |
|
|
| 497 |
|
|
| 498 |
|
\begin{figure} |
| 584 |
|
|
| 585 |
|
\bibliography{iceWater} |
| 586 |
|
|
| 587 |
+ |
There is significant interest in the properties of ice/ice and ice/water |
| 588 |
+ |
interfaces in the geophysics community. Most commonly, the results of shearing |
| 589 |
+ |
two ice blocks past one |
| 590 |
+ |
another\cite{Casassa91, Sukhorukov13, Pritchard12, Lishman13} or the shearing |
| 591 |
+ |
of ice through water\cite{Cuffey99, Bell08}. Using molecular dynamics |
| 592 |
+ |
simulations, Samadashvili has recently shown that when two smooth ice slabs |
| 593 |
+ |
slide past one another, a stable liquid-like layer develops between |
| 594 |
+ |
them\cite{Samadashvili13}. To fundamentally understand these processes, a |
| 595 |
+ |
molecular understanding of the ice/water interfaces is needed. |
| 596 |
+ |
|
| 597 |
+ |
Investigation of the ice/water interface is also crucial in understanding |
| 598 |
+ |
processes such as nucleation, crystal |
| 599 |
+ |
growth,\cite{Han92, Granasy95, Vanfleet95} and crystal |
| 600 |
+ |
melting\cite{Weber83, Han92, Sakai96, Sakai96B}. Insight gained to these |
| 601 |
+ |
properties can also be applied to biological systems of interest, such as |
| 602 |
+ |
the behavior of the antifreeze protein found in winter |
| 603 |
+ |
flounder,\cite{Wierzbicki07,Chapsky97} and certain terrestial |
| 604 |
+ |
arthropods.\cite{Duman:2001qy,Meister29012013} Elucidating the properties which |
| 605 |
+ |
give rise to these processes through experimental techniques can be expensive, |
| 606 |
+ |
complicated, and sometimes infeasible. However, through the use of molecular |
| 607 |
+ |
dynamics simulations much of the problems of investigating these properties |
| 608 |
+ |
are alleviated. |
| 609 |
+ |
|
| 610 |
+ |
Understanding ice/water interfaces inherently begins with the isolated |
| 611 |
+ |
systems. There has been extensive work parameterizing models for liquid water, |
| 612 |
+ |
such as the SPC\cite{Berendsen81}, SPC/E\cite{Berendsen87}, |
| 613 |
+ |
TIP4P\cite{Jorgensen85}, TIP4P/2005\cite{Abascal05}, |
| 614 |
+ |
($\dots$), and more recently, models for simulating |
| 615 |
+ |
the solid phases of water, such as the TIP4P/Ice\cite{Abascal05b} model. The |
| 616 |
+ |
melting point of various crystal structures of ice have been calculated for |
| 617 |
+ |
many of these models |
| 618 |
+ |
(SPC\cite{Karim90,Abascal07}, SPC/E\cite{Baez95,Arbuckle02,Gay02,Bryk02,Bryk04b,Sanz04b,Gernandez06,Abascal07,Vrbka07}, TIP4P\cite{Karim88,Gao00,Sanz04,Sanz04b,Koyama04,Wang05,Fernandez06,Abascal07}, TIP5P\cite{Sanz04,Koyama04,Wang05,Fernandez06,Abascal07}), |
| 619 |
+ |
and the partial or complete phase diagram for the model has been determined |
| 620 |
+ |
(SPC/E\cite{Baez95,Bryk04b,Sanz04b}, TIP4P\cite{Sanz04,Sanz04b,Koyama04}, TIP5P\cite{Sanz04,Koyama04}). |
| 621 |
+ |
Knowing the behavior and melting point for these models has enabled an initial |
| 622 |
+ |
investigation of ice/water interfaces. |
| 623 |
+ |
|
| 624 |
+ |
The Ice-I$_\mathrm{h}$/water quiescent interface has been extensively studied |
| 625 |
+ |
over the past 30 years by theory and experiment. Haymet \emph{et al.} have |
| 626 |
+ |
done significant work characterizing and quantifying the width of these |
| 627 |
+ |
interfaces for the SPC,\cite{Karim90} SPC/E,\cite{Gay02,Bryk02}, |
| 628 |
+ |
CF1,\cite{Hayward01,Hayward02} and TIP4P\cite{Karim88} models for water. In |
| 629 |
+ |
recent years, Haymet has focused on investigating the effects cations and |
| 630 |
+ |
anions have on crystal nucleaion and |
| 631 |
+ |
melting.\cite{Bryk04,Smith05,Wilson08,Wilson10} Nada and Furukawa have studied |
| 632 |
+ |
the the basal- and prismatic-water interface width\cite{Nada95}, crystal |
| 633 |
+ |
surface restructuring at temperatures approaching the melting |
| 634 |
+ |
point\cite{Nada00}, and the mechanism of ice growth inhibition by antifreeze |
| 635 |
+ |
proteins\cite{Nada08,Nada11,Nada12}. Nada has developed a six-site water model |
| 636 |
+ |
for ice/water interfaces near the melting point\cite{Nada03}, and studied the |
| 637 |
+ |
dependence of crystal growth shape on applied pressure\cite{Nada11b}. Using |
| 638 |
+ |
this model, Nada and Furukawa have established differential |
| 639 |
+ |
growth rates for the basal, prismatic, and secondary prismatic facets of |
| 640 |
+ |
Ice-I$_\mathrm{h}$ and found their origins due to a reordering of the hydrogen |
| 641 |
+ |
bond network in water near the interface\cite{Nada05}. While the work |
| 642 |
+ |
described so far has mainly focused on bulk water on ice, there is significant |
| 643 |
+ |
interest in thin films of water on ice surfaces as well. |
| 644 |
+ |
|
| 645 |
+ |
It is well known that the surface of ice exhibits a premelting layer at |
| 646 |
+ |
temperatures near the melting point, often called a quasi-liquid layer (QLL). |
| 647 |
+ |
Molecular dynamics simulations of the facets of ice-I$_\mathrm{h}$ exposed |
| 648 |
+ |
to vacuum performed by Conde, Vega and Patrykiejew have found QLL widths of |
| 649 |
+ |
approximately 10 \AA\ at 3 K below the melting point\cite{Conde08}. |
| 650 |
+ |
Similarly, Limmer and Chandler have used course grain simulations and |
| 651 |
+ |
statistical field theory to estimated QLL widths at the same temperature to |
| 652 |
+ |
be about 3 nm\cite{Limmer14}. |
| 653 |
+ |
Recently, Sazaki and Furukawa have developed an experimental technique with |
| 654 |
+ |
sufficient spatial and temporal resolution to visulaize and quantitatively |
| 655 |
+ |
analyze QLLs on ice crystals at temperatures near melting\cite{Sazaki10}. They |
| 656 |
+ |
have found the width of the QLLs perpindicular to the surface at -2.2$^{o}$C |
| 657 |
+ |
to be $\mathcal{O}$(\AA). They have also seen the formation of two immiscible |
| 658 |
+ |
QLLs, which displayed different stabilities and dynamics on the crystal |
| 659 |
+ |
surface\cite{Sazaki12}. Knowledge of the hydrophilicities of each |
| 660 |
+ |
of the crystal facets would help further our understanding of the properties |
| 661 |
+ |
and dynamics of the QLLs. |
| 662 |
+ |
|
| 663 |
+ |
Presented here is the follow up to our previous paper\cite{Louden13}, in which |
| 664 |
+ |
the basal and prismatic facets of an ice-I$_\mathrm{h}$/water interface were |
| 665 |
+ |
investigated where the ice was sheared relative to the liquid. By using a |
| 666 |
+ |
recently developed velocity shearing and scaling approach to reverse |
| 667 |
+ |
non-equilibrium molecular dynamics (VSS-RNEMD), simultaneous temperature and |
| 668 |
+ |
velocity gradients can be applied to the system, which allows for measurment |
| 669 |
+ |
of friction and thermal transport properties while maintaining a stable |
| 670 |
+ |
interfacial temperature\cite{Kuang12}. Structural analysis and dynamic |
| 671 |
+ |
correlation functions were used to probe the interfacial response to a shear, |
| 672 |
+ |
and the resulting solid/liquid kinetic friction coefficients were reported. |
| 673 |
+ |
In this paper we present the same analysis for the pyramidal and secondary |
| 674 |
+ |
prismatic facets, and show that the differential interfacial friction |
| 675 |
+ |
coefficients for the four facets of ice-I$_\mathrm{h}$ are determined by their |
| 676 |
+ |
relative hydrophilicity by means of dynamics water contact angle simulations. |
| 677 |
+ |
|
| 678 |
|
\end{document} |
| 679 |
+ |
|
| 680 |
+ |
|
