@@ -37,7 +37,7 @@ except that they are specifically designed for the four-point water model. As a
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LAMMPS automatically creates a four-point water molecule, assigning type O
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atoms as oxygen and type H atoms as hydrogen. The fourth massless atom (M) of the
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TIP4P water molecule does not have to be defined explicitly, and the value of
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- :math: `0.1546 \,\text {\AA {} }` corresponds to the O-M distance of the
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+ :math: `0.1546 \,\text {Å }` corresponds to the O-M distance of the
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TIP4P-2005 water model :cite: `abascal2005general `. All other atoms in the simulation
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are treated as usual, with long-range Coulomb interactions. Another novelty, here, is
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the use of ``kspace modify slab 3.0 `` that is combined with the non-periodic
@@ -51,9 +51,8 @@ Let us create the box and the label maps by adding the following lines to **crea
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lattice fcc 4.04
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region box block -3 3 -3 3 -5 5
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- create_box 5 box bond/types 1 angle/types 1 &
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- extra/bond/per/atom 2 extra/angle/per/atom 1 &
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- extra/special/per/atom 2
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+ create_box 5 box bond/types 1 angle/types 1 extra/bond/per/atom 2 extra/angle/per/atom 1 &
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+ extra/special/per/atom 2
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labelmap atom 1 O 2 H 3 Na+ 4 Cl- 5 WALL
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labelmap bond 1 O-H
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labelmap angle 1 H-O-H
@@ -62,7 +61,7 @@ The ``lattice`` command defines the unit cell. Here, the face-centered cubic (f
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with a scale factor of 4.04 has been chosen for the future positioning of the atoms
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of the walls. The ``region `` command defines a geometric region of space. By choosing
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:math: `\text {xlo}=-3 ` and :math: `\text {xlo}=3 `, and because we have previously chosen a lattice with a scale
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- factor of 4.04, the region box extends from :math: `-12.12 ~\text {\AA {}} ` to :math: `12.12 ~\text {\AA {} }`
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+ factor of 4.04, the region box extends from :math: `-12.12 ~\text {Å} ` to :math: `12.12 ~\text {Å }`
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along the :math: `x` direction. The ``create_box `` command creates a simulation box with
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5 types of atoms: the oxygen and hydrogen of the water molecules, the two ions (:math: `\text {Na}^+`,
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:math: `\text {Cl}^-`), and the atoms from the walls. The simulation contains 1 type of bond
@@ -87,12 +86,15 @@ following lines to **create.lmp**:
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Atoms will be placed in the positions of the previously defined lattice, thus
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forming fcc solids.
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- To add the water molecules, the molecule
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- template called \h ref{\f ilepath tutorial4/water.mol}{\d wlcmd{water.mol}}
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+ To add the water molecules, the molecule template called |water_mol_4 |
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must be located next to **create.lmp **. The template contains all the
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necessary information concerning the water molecule, such as atom positions,
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bonds, and angles. Add the following lines to **create.lmp **:
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+ .. |water_mol_4 | raw :: html
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+
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+ <a href="../../../../../.dependencies/lammpstutorials-inputs/tutorial4/water.mol" target="_blank">water.mol</a>
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+
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.. code-block :: lammps
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region rliquid block INF INF INF INF -2 2
@@ -138,11 +140,16 @@ lines into **create.lmp**:
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include parameters.inc
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include groups.inc
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- Both \h ref{\f ilepath tutorial4/parameters.inc}{\d wlcmd{parameters.inc}}
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- and \h ref{\f ilepath tutorial4/groups.inc}{\d wlcmd{groups.inc}} files
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- must be located next to **create.lmp **.
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+ Both |parameters_inc_4 | and |groups_inc_4 | files
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+ must be located next to **create.lmp **. The **parameters.inc ** file contains the masses, as follows:
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+
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+ .. |parameters_inc_4 | raw :: html
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+
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+ <a href="../../../../../.dependencies/lammpstutorials-inputs/tutorial4/parameters.inc" target="_blank">parameters.inc</a>
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- The **parameters.inc ** file contains the masses, as follows:
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+ .. |groups_inc_4 | raw :: html
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+
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+ <a href="../../../../../.dependencies/lammpstutorials-inputs/tutorial4/groups.inc" target="_blank">groups.inc</a>
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.. code-block :: lammps
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@@ -182,14 +189,15 @@ to make the walls less hydrophilic, the value of
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:math: `\epsilon _\text {O-WALL}` was reduced.
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Finally, the **parameters.inc ** file contains the following two lines:
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+
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.. code-block :: lammps
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bond_coeff O-H 0 0.9572
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angle_coeff H-O-H 0 104.52
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The ``bond_coeff `` command, used here for the O-H bond of the water
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molecule, sets both the spring constant of the harmonic potential and the
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- equilibrium bond distance of :math: `0.9572 ~\text {\AA {} }`. The constant can be 0 for a
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+ equilibrium bond distance of :math: `0.9572 ~\text {Å }`. The constant can be 0 for a
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rigid water molecule because the SHAKE algorithm will maintain the rigid
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structure of the water molecule (see below) :cite: `ryckaert1977numerical, andersen1983rattle `.
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Similarly, the ``angle_coeff `` command for the H-O-H angle of the water molecule sets
@@ -208,7 +216,7 @@ several ``group`` commands to selects atoms based on their types:
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group fluid union H2O ions
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The **groups.inc ** file also defines the ``walltop `` and ``wallbot ``
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- groups, which contain the WALL atoms located in the :math: `z > 0 ` and :math: `z < 0 ` regions, respectively::
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+ groups, which contain the WALL atoms located in the :math: `z > 0 ` and :math: `z < 0 ` regions, respectively:
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.. code-block :: lammps
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@@ -228,7 +236,6 @@ to delete about :math:`15~\%` of the water molecules:
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delete_atoms random fraction 0.15 yes H2O NULL 482793 mol yes
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-
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To create an image of the system, add the following ``dump `` image
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into **create.lmp ** (see also Fig.~\r ef{fig:NANOSHEAR-system}):
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@@ -525,7 +532,7 @@ along :math:`x` (``vx``) within the bins. Add the following lines to **shearing
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run 200000
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- Here, a bin size of :math: `0.25 \,\text {\AA {} }` is used for the density
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+ Here, a bin size of :math: `0.25 \,\text {Å }` is used for the density
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profiles generated by the ``ave/chunk `` commands, and three
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**.dat ** files are created for the water, the walls, and the ions,
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respectively. With values of ``10 15000 200000 ``, the velocity
@@ -552,7 +559,7 @@ the fluid on the shearing wall, and :math:`\dot{\gamma}` the shear rate
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:cite: `gravelle2021violations `. Here, the shear rate is
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approximately :math: `\dot {\gamma } = 20 \cdot 10 ^9 \,\text {s}^{-1 }` (Fig.~\r ef{fig:NANOSHEAR-profiles}),
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the average force on each wall is given by ``f_mysf1[1] `` and ``f_mysf2[1] ``
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- and is approximately :math: `2.7 \,\mathrm {kcal/mol/\AA }` in magnitude. Using a surface area
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+ and is approximately :math: `2.7 \,\mathrm {kcal/mol/Å }` in magnitude. Using a surface area
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for the walls of :math: `A = 6 \cdot 10 ^{-18 }\,\text {m}^2 `, one obtains an estimate for
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the shear viscosity for the confined fluid of :math: `\eta = 3.1 \,\text {mPa.s}` using Eq.~\e qref{eq:eta}.
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