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			<div class="section" id="replicate-command">
			<span id="index-0"></span><h1>replicate command<a class="headerlink" href="#replicate-command" title="Permalink to this headline">¶</a></h1>
			<div class="section" id="syntax">
			<h2>Syntax<a class="headerlink" href="#syntax" title="Permalink to this headline">¶</a></h2>
			<div class="highlight-python"><div class="highlight"><pre>replicate nx ny nz
			</pre></div>
			</div>
			<ul class="simple">
			<li>nx,ny,nz = replication factors in each dimension</li>
			</ul>
			</div>
			<div class="section" id="examples">
			<h2>Examples<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h2>
			<div class="highlight-python"><div class="highlight"><pre>replicate 2 3 2
			</pre></div>
			</div>
			</div>
			<div class="section" id="description">
			<h2>Description<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2>
			<p>Replicate the current simulation one or more times in each dimension.
			For example, replication factors of 2,2,2 will create a simulation
			with 8x as many atoms by doubling the simulation domain in each
			dimension. A replication factor of 1 in a dimension leaves the
			simulation domain unchanged. When the new simulation box is created
			it is also partitioned into a regular 3d grid of rectangular bricks,
			one per processor, based on the number of processors being used and
			the settings of the <a class="reference internal" href="processors.html"><em>processors</em></a> command. The
			partitioning can later be changed by the <a class="reference internal" href="balance.html"><em>balance</em></a> or
			<a class="reference internal" href="fix_balance.html"><em>fix balance</em></a> commands.</p>
			<p>All properties of the atoms are replicated, including their
			velocities, which may or may not be desirable. New atom IDs are
			assigned to new atoms, as are molecule IDs. Bonds and other topology
			interactions are created between pairs of new atoms as well as between
			old and new atoms. This is done by using the image flag for each atom
			to “unwrap” it out of the periodic box before replicating it.</p>
			<p>This means that any molecular bond you specify in the original data
			file that crosses a periodic boundary should be between two atoms with
			image flags that differ by 1. This will allow the bond to be
			unwrapped appropriately.</p>
			</div>
			<div class="section" id="restrictions">
			<h2>Restrictions<a class="headerlink" href="#restrictions" title="Permalink to this headline">¶</a></h2>
			<p>A 2d simulation cannot be replicated in the z dimension.</p>
			<p>If a simulation is non-periodic in a dimension, care should be used
			when replicating it in that dimension, as it may put atoms nearly on
			top of each other.</p>
			<div class="admonition note">
			<p class="first admonition-title">Note</p>
			<p class="last">You cannot use the replicate command on a system which has a
			molecule that spans the box and is bonded to itself across a periodic
			boundary, so that the molecule is efffectively a loop. A simple
			example would be a linear polymer chain that spans the simulation box
			and bonds back to itself across the periodic boundary. More realistic
			examples would be a CNT (meant to be an infinitely long CNT) or a
			graphene sheet or a bulk periodic crystal where there are explicit
			bonds specified between near neighbors. (Note that this only applies
			to systems that have permanent bonds as specified in the data file. A
			CNT that is just atoms modeled with the <a class="reference internal" href="pair_airebo.html"><em>AIREBO potential</em></a> has no such permanent bonds, so it can be
			replicated.) The reason replication does not work with those systems
			is that the image flag settings described above cannot be made
			consistent. I.e. it is not possible to define images flags so that
			when every pair of bonded atoms is unwrapped (using the image flags),
			they will be close to each other. The only way the replicate command
			could work in this scenario is for it to break a bond, insert more
			atoms, and re-connect the loop for the larger simulation box. But it
			is not clever enough to do this. So you will have to construct a
			larger version of your molecule as a pre-processing step and input a
			new data file to LAMMPS.</p>
			</div>
			<p>If the current simulation was read in from a restart file (before a
			run is performed), there can have been no fix information stored in
			the file for individual atoms. Similarly, no fixes can be defined at
			the time the replicate command is used that require vectors of atom
			information to be stored. This is because the replicate command does
			not know how to replicate that information for new atoms it creates.</p>
			<p>Replicating a system that has rigid bodies (defined via the <a class="reference internal" href="fix_rigid.html"><em>fix rigid</em></a> command), either currently defined or that
			created the restart file which was read in before replicating, can
			cause problems if there is a bond between a pair of rigid bodies that
			straddle a periodic boundary. This is because the periodic image
			information for particles in the rigid bodies are set differently than
			for a non-rigid system and can result in a new bond being created that
			spans the periodic box. Thus you cannot use the replicate command in
			this scenario.</p>
			<p><strong>Related commands:</strong> none</p>
			<p><strong>Default:</strong> none</p>
			</div>
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