fix_wall_ees.txt
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fix_wall_ees.txt
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			"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c

			:link(lws,http://lammps.sandia.gov)
			:link(ld,Manual.html)
			:link(lc,Section_commands.html#comm)

			:line

			fix wall/ees command :h3


			[Syntax:]

			fix ID group-ID wall/ees face args ... keyword value ... :pre

			ID, group-ID are documented in "fix"_fix.html command :ulb,l
			one or more face/arg pairs may be appended :l
			face = {xlo} or {xhi} or {ylo} or {yhi} or {zlo} or {zhi} :l
			args = coord epsilon sigma cutoff
			coord = position of wall = EDGE or constant or variable
			EDGE = current lo or hi edge of simulation box
			constant = number like 0.0 or -30.0 (distance units)
			variable = "equal-style variable"_variable.html like v_x or v_wiggle
			epsilon = strength factor for wall-particle interaction (energy or energy/distance^2 units)
			epsilon can be a variable (see below)
			sigma = size factor for wall-particle interaction (distance units)
			sigma can be a variable (see below)
			cutoff = distance from wall at which wall-particle interaction is cut off (distance units) :pre
			zero or more keyword/value pairs may be appended :l
			keyword = {units} or {fld} :l
			{units} value = {lattice} or {box}
			{lattice} = the wall position is defined in lattice units
			{box} = the wall position is defined in simulation box units
			{fld} value = {yes} or {no}
			{yes} = invoke the wall constraint to be compatible with implicit FLD
			{no} = invoke the wall constraint in the normal way
			{pbc} value = {yes} or {no}
			{yes} = allow periodic boundary in a wall dimension
			{no} = require non-perioidic boundaries in any wall dimension :pre
			:ule

			[Examples:]

			fix wallhi all wall/ees xlo -1.0 1.0 1.0 2.5 units box
			fix wallhi all wall/ees xhi EDGE 1.0 1.0 2.5
			fix wallhi all wall/ees v_wiggle 23.2 1.0 1.0 2.5
			fix zwalls all wall/ees zlo 0.0 1.0 1.0 0.858 zhi 40.0 1.0 1.0 0.858 :pre

			[Description:]

			Bound the simulation domain on one or more of its faces with a flat
			wall that interacts with the ellipsoidal atoms in the group by generating a force
			on the atom in a direction perpendicular to the wall and a torque parallel with the wall. The energy of
			wall-particle interactions E is given by:




			:c,image(Eqs/fix_wall_ees.jpg)


			Introduced by Babadi and Ejtehadi in "(Babadi)"_#BabadiEjtehadi. Here, {r} is the distance from the particle to the wall at
			position {coord}, and Rc is the {cutoff} distance at which the
			particle and wall no longer interact. Also, sigma_n is the distance between center of ellipsoid and the nearest point of its surface to the wall The energy of the wall (see the image below).

			:c,image(JPG/fix_wall_ees_image.jpg)


			Details of using this command and specifications are the same as fix/wall command. You can also find an example in USER/ees/ under examples/ directory.

			The prefactor {epsilon} can be thought of as an
			effective Hamaker constant with energy units for the strength of the
			ellipsoid-wall interaction. More specifically, the {epsilon} pre-factor
			= 8 * pi^2 * rho_wall * rho_ellipsoid * epsilon * sigma_a * sigma_b * sigma_c, where epsilon
			is the LJ parameters for the constituent LJ
			particles and sigma_a, sigma_b, and sigma_c are radii of ellipsoidal particles. Rho_wall and rho_ellipsoid are the number density of the
			constituent particles, in the wall and ellipsoid respectively, in units
			of 1/volume.

			NOTE: You must insure that r is always bigger than sigma_n for
			all particles in the group, or LAMMPS will generate an error. This
			means you cannot start your simulation with particles touching the wall
			position {coord} (r = sigma_n) or with particles penetrating the wall (0 =< r < sigma_n) or with particles on the wrong side of the
			wall (r < 0).

			[Restrictions:]

			This fix is part of the USER-MISC package. It is only enabled if LAMMPS
			was built with that package. See the "Making
			LAMMPS"_Section_start.html#start_3 section for more info.

			This fix requires that atoms be ellipsoids as defined by the
			"atom_style ellipsoid"_atom_style.html command.

			[Related commands:]

			"fix wall"_fix_wall.html,
			"pair resquared"_pair_resquared.html

			[Default:]

			The option defaults units = lattice, fld = no, and pbc = no.

			:line

			:link(BabadiEjtehadi)
			[(Babadi)] Babadi and Ejtehadi, EPL, 77 (2007) 23002.
			:link(Babadi)
			[(Berardi)] Babadi, Ejtehadi, Everaers, J Comp Phys, 219, 770-779 (2006).

lammps/doc/src/fix_wall_ees.txtb720f391637bmaster

fix_wall_ees.txtView Options

lammps/doc/src/fix_wall_ees.txt
b720f391637bmaster

fix_wall_ees.txt
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