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edca6eb4dbf98a7d8853bf04cbce2331bf25d7c2
lammps/doc/html/hyper.html
Barak Hirshberg edca6eb4db this is a lost cause
2025-01-13 14:55:48 +00:00

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<title>hyper command &mdash; LAMMPS documentation</title>
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<div class="lammps_version">Version: <b>19 Nov 2024</b></div>
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<p class="caption" role="heading"><span class="caption-text">User Guide</span></p>
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<li class="toctree-l1"><a class="reference internal" href="Intro.html">1. Introduction</a></li>
<li class="toctree-l1"><a class="reference internal" href="Install.html">2. Install LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Build.html">3. Build LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Run_head.html">4. Run LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Commands.html">5. Commands</a></li>
<li class="toctree-l1"><a class="reference internal" href="Packages.html">6. Optional packages</a></li>
<li class="toctree-l1"><a class="reference internal" href="Speed.html">7. Accelerate performance</a></li>
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<li class="toctree-l1"><a class="reference internal" href="Tools.html">10. Auxiliary tools</a></li>
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<p class="caption" role="heading"><span class="caption-text">Programmer Guide</span></p>
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<li class="toctree-l1"><a class="reference internal" href="Library.html">1. LAMMPS Library Interfaces</a></li>
<li class="toctree-l1"><a class="reference internal" href="Python_head.html">2. Use Python with LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Modify.html">3. Modifying &amp; extending LAMMPS</a></li>
<li class="toctree-l1"><a class="reference internal" href="Developer.html">4. Information for Developers</a></li>
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<p class="caption" role="heading"><span class="caption-text">Command Reference</span></p>
<ul class="current">
<li class="toctree-l1 current"><a class="reference internal" href="commands_list.html">Commands</a><ul class="current">
<li class="toctree-l2"><a class="reference internal" href="angle_coeff.html">angle_coeff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="angle_style.html">angle_style command</a></li>
<li class="toctree-l2"><a class="reference internal" href="angle_write.html">angle_write command</a></li>
<li class="toctree-l2"><a class="reference internal" href="atom_modify.html">atom_modify command</a></li>
<li class="toctree-l2"><a class="reference internal" href="atom_style.html">atom_style command</a></li>
<li class="toctree-l2"><a class="reference internal" href="balance.html">balance command</a></li>
<li class="toctree-l2"><a class="reference internal" href="bond_coeff.html">bond_coeff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="bond_style.html">bond_style command</a></li>
<li class="toctree-l2"><a class="reference internal" href="bond_write.html">bond_write command</a></li>
<li class="toctree-l2"><a class="reference internal" href="boundary.html">boundary command</a></li>
<li class="toctree-l2"><a class="reference internal" href="change_box.html">change_box command</a></li>
<li class="toctree-l2"><a class="reference internal" href="clear.html">clear command</a></li>
<li class="toctree-l2"><a class="reference internal" href="comm_modify.html">comm_modify command</a></li>
<li class="toctree-l2"><a class="reference internal" href="comm_style.html">comm_style command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute.html">compute command</a></li>
<li class="toctree-l2"><a class="reference internal" href="compute_modify.html">compute_modify command</a></li>
<li class="toctree-l2"><a class="reference internal" href="create_atoms.html">create_atoms command</a></li>
<li class="toctree-l2"><a class="reference internal" href="create_bonds.html">create_bonds command</a></li>
<li class="toctree-l2"><a class="reference internal" href="create_box.html">create_box command</a></li>
<li class="toctree-l2"><a class="reference internal" href="delete_atoms.html">delete_atoms command</a></li>
<li class="toctree-l2"><a class="reference internal" href="delete_bonds.html">delete_bonds command</a></li>
<li class="toctree-l2"><a class="reference internal" href="dielectric.html">dielectric command</a></li>
<li class="toctree-l2"><a class="reference internal" href="dihedral_coeff.html">dihedral_coeff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="dihedral_style.html">dihedral_style command</a></li>
<li class="toctree-l2"><a class="reference internal" href="dihedral_write.html">dihedral_write command</a></li>
<li class="toctree-l2"><a class="reference internal" href="dimension.html">dimension command</a></li>
<li class="toctree-l2"><a class="reference internal" href="displace_atoms.html">displace_atoms command</a></li>
<li class="toctree-l2"><a class="reference internal" href="dynamical_matrix.html">dynamical_matrix command</a></li>
<li class="toctree-l2"><a class="reference internal" href="echo.html">echo command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix.html">fix command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fix_modify.html">fix_modify command</a></li>
<li class="toctree-l2"><a class="reference internal" href="fitpod_command.html">fitpod command</a></li>
<li class="toctree-l2"><a class="reference internal" href="geturl.html">geturl command</a></li>
<li class="toctree-l2"><a class="reference internal" href="group.html">group command</a></li>
<li class="toctree-l2"><a class="reference internal" href="group2ndx.html">group2ndx command</a></li>
<li class="toctree-l2"><a class="reference internal" href="group2ndx.html#ndx2group-command">ndx2group command</a></li>
<li class="toctree-l2 current"><a class="current reference internal" href="#">hyper command</a><ul>
<li class="toctree-l3"><a class="reference internal" href="#syntax">Syntax</a></li>
<li class="toctree-l3"><a class="reference internal" href="#examples">Examples</a></li>
<li class="toctree-l3"><a class="reference internal" href="#description">Description</a></li>
<li class="toctree-l3"><a class="reference internal" href="#restrictions">Restrictions</a></li>
<li class="toctree-l3"><a class="reference internal" href="#related-commands">Related commands</a></li>
<li class="toctree-l3"><a class="reference internal" href="#default">Default</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="if.html">if command</a></li>
<li class="toctree-l2"><a class="reference internal" href="improper_coeff.html">improper_coeff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="improper_style.html">improper_style command</a></li>
<li class="toctree-l2"><a class="reference internal" href="include.html">include command</a></li>
<li class="toctree-l2"><a class="reference internal" href="info.html">info command</a></li>
<li class="toctree-l2"><a class="reference internal" href="jump.html">jump command</a></li>
<li class="toctree-l2"><a class="reference internal" href="kim_commands.html">kim command</a></li>
<li class="toctree-l2"><a class="reference internal" href="kspace_modify.html">kspace_modify command</a></li>
<li class="toctree-l2"><a class="reference internal" href="kspace_style.html">kspace_style command</a></li>
<li class="toctree-l2"><a class="reference internal" href="label.html">label command</a></li>
<li class="toctree-l2"><a class="reference internal" href="labelmap.html">labelmap command</a></li>
<li class="toctree-l2"><a class="reference internal" href="lattice.html">lattice command</a></li>
<li class="toctree-l2"><a class="reference internal" href="log.html">log command</a></li>
<li class="toctree-l2"><a class="reference internal" href="mass.html">mass command</a></li>
<li class="toctree-l2"><a class="reference internal" href="mdi.html">mdi command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_modify.html">min_modify command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_spin.html">min_style spin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_spin.html#min-style-spin-cg-command">min_style spin/cg command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_spin.html#min-style-spin-lbfgs-command">min_style spin/lbfgs command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_style.html">min_style cg command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_style.html#min-style-hftn-command">min_style hftn command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_style.html#min-style-sd-command">min_style sd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_style.html#min-style-quickmin-command">min_style quickmin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_style.html#min-style-fire-command">min_style fire command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_style.html#min-style-spin-command"><span class="xref std std-doc">min_style spin</span> command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_style.html#min-style-spin-cg-command"><span class="xref std std-doc">min_style spin/cg</span> command</a></li>
<li class="toctree-l2"><a class="reference internal" href="min_style.html#min-style-spin-lbfgs-command"><span class="xref std std-doc">min_style spin/lbfgs</span> command</a></li>
<li class="toctree-l2"><a class="reference internal" href="minimize.html">minimize command</a></li>
<li class="toctree-l2"><a class="reference internal" href="molecule.html">molecule command</a></li>
<li class="toctree-l2"><a class="reference internal" href="neb.html">neb command</a></li>
<li class="toctree-l2"><a class="reference internal" href="neb_spin.html">neb/spin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="neigh_modify.html">neigh_modify command</a></li>
<li class="toctree-l2"><a class="reference internal" href="neighbor.html">neighbor command</a></li>
<li class="toctree-l2"><a class="reference internal" href="newton.html">newton command</a></li>
<li class="toctree-l2"><a class="reference internal" href="next.html">next command</a></li>
<li class="toctree-l2"><a class="reference internal" href="package.html">package command</a></li>
<li class="toctree-l2"><a class="reference internal" href="pair_coeff.html">pair_coeff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="pair_modify.html">pair_modify command</a></li>
<li class="toctree-l2"><a class="reference internal" href="pair_style.html">pair_style command</a></li>
<li class="toctree-l2"><a class="reference internal" href="pair_write.html">pair_write command</a></li>
<li class="toctree-l2"><a class="reference internal" href="partition.html">partition command</a></li>
<li class="toctree-l2"><a class="reference internal" href="plugin.html">plugin command</a></li>
<li class="toctree-l2"><a class="reference internal" href="prd.html">prd command</a></li>
<li class="toctree-l2"><a class="reference internal" href="print.html">print command</a></li>
<li class="toctree-l2"><a class="reference internal" href="processors.html">processors command</a></li>
<li class="toctree-l2"><a class="reference internal" href="python.html">python command</a></li>
<li class="toctree-l2"><a class="reference internal" href="quit.html">quit command</a></li>
<li class="toctree-l2"><a class="reference internal" href="read_data.html">read_data command</a></li>
<li class="toctree-l2"><a class="reference internal" href="read_dump.html">read_dump command</a></li>
<li class="toctree-l2"><a class="reference internal" href="read_restart.html">read_restart command</a></li>
<li class="toctree-l2"><a class="reference internal" href="region.html">region command</a></li>
<li class="toctree-l2"><a class="reference internal" href="replicate.html">replicate command</a></li>
<li class="toctree-l2"><a class="reference internal" href="rerun.html">rerun command</a></li>
<li class="toctree-l2"><a class="reference internal" href="reset_atoms.html">reset_atoms command</a></li>
<li class="toctree-l2"><a class="reference internal" href="reset_timestep.html">reset_timestep command</a></li>
<li class="toctree-l2"><a class="reference internal" href="restart.html">restart command</a></li>
<li class="toctree-l2"><a class="reference internal" href="run.html">run command</a></li>
<li class="toctree-l2"><a class="reference internal" href="run_style.html">run_style command</a></li>
<li class="toctree-l2"><a class="reference internal" href="set.html">set command</a></li>
<li class="toctree-l2"><a class="reference internal" href="shell.html">shell command</a></li>
<li class="toctree-l2"><a class="reference internal" href="special_bonds.html">special_bonds command</a></li>
<li class="toctree-l2"><a class="reference internal" href="suffix.html">suffix command</a></li>
<li class="toctree-l2"><a class="reference internal" href="tad.html">tad command</a></li>
<li class="toctree-l2"><a class="reference internal" href="temper.html">temper command</a></li>
<li class="toctree-l2"><a class="reference internal" href="temper_grem.html">temper/grem command</a></li>
<li class="toctree-l2"><a class="reference internal" href="temper_npt.html">temper/npt command</a></li>
<li class="toctree-l2"><a class="reference internal" href="thermo.html">thermo command</a></li>
<li class="toctree-l2"><a class="reference internal" href="thermo_modify.html">thermo_modify command</a></li>
<li class="toctree-l2"><a class="reference internal" href="thermo_style.html">thermo_style command</a></li>
<li class="toctree-l2"><a class="reference internal" href="third_order.html">third_order command</a></li>
<li class="toctree-l2"><a class="reference internal" href="timer.html">timer command</a></li>
<li class="toctree-l2"><a class="reference internal" href="timestep.html">timestep command</a></li>
<li class="toctree-l2"><a class="reference internal" href="uncompute.html">uncompute command</a></li>
<li class="toctree-l2"><a class="reference internal" href="undump.html">undump command</a></li>
<li class="toctree-l2"><a class="reference internal" href="unfix.html">unfix command</a></li>
<li class="toctree-l2"><a class="reference internal" href="units.html">units command</a></li>
<li class="toctree-l2"><a class="reference internal" href="variable.html">variable command</a></li>
<li class="toctree-l2"><a class="reference internal" href="velocity.html">velocity command</a></li>
<li class="toctree-l2"><a class="reference internal" href="write_coeff.html">write_coeff command</a></li>
<li class="toctree-l2"><a class="reference internal" href="write_data.html">write_data command</a></li>
<li class="toctree-l2"><a class="reference internal" href="write_dump.html">write_dump command</a></li>
<li class="toctree-l2"><a class="reference internal" href="write_restart.html">write_restart command</a></li>
</ul>
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<li class="toctree-l1"><a class="reference internal" href="fixes.html">Fix Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="computes.html">Compute Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="pairs.html">Pair Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="bonds.html">Bond Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="angles.html">Angle Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="dihedrals.html">Dihedral Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="impropers.html">Improper Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="dumps.html">Dump Styles</a></li>
<li class="toctree-l1"><a class="reference internal" href="fix_modify_atc_commands.html">fix_modify AtC commands</a></li>
<li class="toctree-l1"><a class="reference internal" href="Bibliography.html">Bibliography</a></li>
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<p><span class="math notranslate nohighlight">\(\renewcommand{\AA}{\text{Å}}\)</span></p>
<section id="hyper-command">
<span id="index-0"></span><h1>hyper command<a class="headerlink" href="#hyper-command" title="Link to this heading"></a></h1>
<section id="syntax">
<h2>Syntax<a class="headerlink" href="#syntax" title="Link to this heading"></a></h2>
<div class="highlight-LAMMPS notranslate"><div class="highlight"><pre><span></span><span class="k">hyper</span><span class="w"> </span><span class="n">N</span><span class="w"> </span><span class="n">Nevent</span><span class="w"> </span><span class="n">fix</span><span class="o">-</span><span class="n">ID</span><span class="w"> </span><span class="n">compute</span><span class="o">-</span><span class="n">ID</span><span class="w"> </span><span class="n">keyword</span><span class="w"> </span><span class="n">values</span><span class="w"> </span><span class="n">...</span>
</pre></div>
</div>
<ul>
<li><p>N = # of timesteps to run</p></li>
<li><p>Nevent = check for events every this many steps</p></li>
<li><p>fix-ID = ID of a fix that applies a global or local bias potential, can be NULL</p></li>
<li><p>compute-ID = ID of a compute that identifies when an event has occurred</p></li>
<li><p>zero or more keyword/value pairs may be appended</p></li>
<li><p>keyword = <em>min</em> or <em>dump</em> or <em>rebond</em></p>
<pre class="literal-block"><em>min</em> values = etol ftol maxiter maxeval
etol = stopping tolerance for energy, used in quenching
ftol = stopping tolerance for force, used in quenching
maxiter = max iterations of minimize, used in quenching
maxeval = max number of force/energy evaluations, used in quenching
<em>dump</em> value = dump-ID
dump-ID = ID of dump to trigger whenever an event takes place
<em>rebond</em> value = Nrebond
Nrebond = frequency at which to reset bonds, even if no event has occurred</pre>
</li>
</ul>
</section>
<section id="examples">
<h2>Examples<a class="headerlink" href="#examples" title="Link to this heading"></a></h2>
<div class="highlight-LAMMPS notranslate"><div class="highlight"><pre><span></span><span class="k">compute </span><span class="nv nv-Identifier">event</span><span class="w"> </span><span class="nv nv-Identifier">all</span><span class="w"> </span><span class="n">event</span><span class="o">/</span><span class="n">displace</span><span class="w"> </span><span class="m">1.0</span>
<span class="k">fix </span><span class="nv nv-Identifier">HG</span><span class="w"> </span><span class="nv nv-Identifier">mobile</span><span class="w"> </span><span class="n">hyper</span><span class="o">/</span><span class="n">global</span><span class="w"> </span><span class="m">3.0</span><span class="w"> </span><span class="m">0.3</span><span class="w"> </span><span class="m">0.4</span><span class="w"> </span><span class="m">800.0</span>
<span class="k">hyper</span><span class="w"> </span><span class="m">5000</span><span class="w"> </span><span class="m">100</span><span class="w"> </span><span class="n">HG</span><span class="w"> </span><span class="n">event</span><span class="w"> </span><span class="n">min</span><span class="w"> </span><span class="m">1.0e-6</span><span class="w"> </span><span class="m">1.0e-6</span><span class="w"> </span><span class="m">100</span><span class="w"> </span><span class="m">100</span><span class="w"> </span><span class="k">dump </span><span class="nv nv-Identifier">1</span><span class="w"> </span><span class="nv nv-Identifier">dump</span><span class="w"> </span><span class="m">5</span>
</pre></div>
</div>
</section>
<section id="description">
<h2>Description<a class="headerlink" href="#description" title="Link to this heading"></a></h2>
<p>Run a bond-boost hyperdynamics (HD) simulation where time is
accelerated by application of a bias potential to one or more pairs of
nearby atoms in the system. This command can be used to run both
global and local hyperdynamics. In global HD a single bond within the
system is biased on each timestep. In local HD multiple bonds
(separated by a sufficient distance) can be biased simultaneously at
each timestep. In the bond-boost hyperdynamics context, a “bond” is
not a covalent bond between a pair of atoms in a molecule. Rather it
is simply a pair of nearby atoms as discussed below.</p>
<p>Both global and local HD are described in <a class="reference internal" href="#voter2013"><span class="std std-ref">(Voter2013)</span></a> by Art Voter and collaborators. Similar to parallel
replica dynamics (PRD), global and local HD are methods for performing
accelerated dynamics that are suitable for infrequent-event systems
that obey first-order kinetics. A good overview of accelerated
dynamics methods (AMD) for such systems in given in <a class="reference internal" href="#voter2002hd"><span class="std std-ref">(Voter2002)</span></a> from the same group. To quote from the review paper:
“The dynamical evolution is characterized by vibrational excursions
within a potential basin, punctuated by occasional transitions between
basins. The transition probability is characterized by p(t) =
k*exp(-kt) where k is the rate constant.”</p>
<p>Both HD and PRD produce a time-accurate trajectory that effectively
extends the timescale over which a system can be simulated, but they
do it differently. HD uses a single replica of the system and
accelerates time by biasing the interaction potential in a manner such
that each timestep is effectively longer. PRD creates Nr replicas of
the system and runs dynamics on each independently with a normal
unbiased potential until an event occurs in one of the replicas. The
time between events is reduced by a factor of Nr replicas. For both
methods, per CPU second, more physical time elapses and more events
occur. See the <a class="reference internal" href="prd.html"><span class="doc">prd</span></a> page for more info about PRD.</p>
<p>An HD run has several stages, which are repeated each time an event
occurs, as explained below. The logic for an HD run is as follows:</p>
<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>quench
create initial list of bonds
while (time remains):
run dynamics for Nevent steps
quench
check for an event
if event occurred: reset list of bonds
restore pre-quench state
</pre></div>
</div>
<p>The list of bonds is the list of atom pairs of atoms that are within a
short cutoff distance of each other after the system energy is
minimized (quenched). This list is created and reset by a <a class="reference internal" href="fix_hyper_global.html"><span class="doc">fix hyper/global</span></a> or <a class="reference internal" href="fix_hyper_local.html"><span class="doc">fix hyper/local</span></a> command specified as <em>fix-ID</em>. At
every dynamics timestep, the same fix selects one of more bonds to
apply a bias potential to.</p>
<div class="admonition note">
<p class="admonition-title">Note</p>
<p>The style of fix associated with the specified <em>fix-ID</em>
determines whether you are running the global versus local
hyperdynamics algorithm.</p>
</div>
<p>Dynamics (with the bias potential) is run continuously, stopping every
<em>Nevent</em> steps to check if a transition event has occurred. The
specified <em>N</em> for total steps must be a multiple of <em>Nevent</em>. check
is performed by quenching the system and comparing the resulting atom
coordinates to the coordinates from the previous basin.</p>
<p>A quench is an energy minimization and is performed by whichever
algorithm has been defined by the <a class="reference internal" href="min_style.html"><span class="doc">min_style</span></a> command.
Minimization parameters may be set via the
<a class="reference internal" href="min_modify.html"><span class="doc">min_modify</span></a> command and by the <em>min</em> keyword of the
hyper command. The latter are the settings that would be used with
the <a class="reference internal" href="minimize.html"><span class="doc">minimize</span></a> command. Note that typically, you do not
need to perform a highly-converged minimization to detect a transition
event, though you may need to in order to prevent a set of atoms in
the system from relaxing to a saddle point.</p>
<p>The event check is performed by a compute with the specified
<em>compute-ID</em>. Currently there is only one compute that works with the
hyper command, which is the <a class="reference internal" href="compute_event_displace.html"><span class="doc">compute event/displace</span></a> command. Other
event-checking computes may be added. <a class="reference internal" href="compute_event_displace.html"><span class="doc">Compute event/displace</span></a> checks whether any atom in
the compute group has moved further than a specified threshold
distance. If so, an event has occurred.</p>
<p>If this happens, the list of bonds is reset, since some bond pairs
are likely now too far apart, and new pairs are likely close enough
to be considered a bond. The pre-quenched state of the
system (coordinates and velocities) is restored, and dynamics continue.</p>
<p>At the end of the hyper run, a variety of statistics are output to the
screen and logfile. These include info relevant to both global and
local hyperdynamics, such as the number of events and the elapsed
hyper time (accelerated time), And it includes info specific to one or
the other, depending on which style of fix was specified by <em>fix-ID</em>.</p>
<hr class="docutils" />
<p>The optional keywords operate as follows.</p>
<p>As explained above, the <em>min</em> keyword can be used to specify
parameters for the quench. Their meaning is the same
as for the <a class="reference internal" href="minimize.html"><span class="doc">minimize</span></a> command</p>
<p>The <em>dump</em> keyword can be used to trigger a specific dump command with
the specified <em>dump-ID</em> to output a snapshot each time an event is
detected. It can be specified multiple times with different <em>dump-ID</em>
values, as in the example above. These snapshots will be for the
quenched state of the system on a timestep that is a multiple of
<em>Nevent</em>, i.e. a timestep after the event has occurred. Note that any
dump command in the input script will also output snapshots at
whatever timestep interval it defines via its <em>N</em> argument; see the
<a class="reference internal" href="dump.html"><span class="doc">dump</span></a> command for details. This means if you only want a
particular dump to output snapshots when events are detected, you
should specify its <em>N</em> as a value larger than the length of the
hyperdynamics run.</p>
<p>As in the code logic above, the bond list is normally only reset when
an event occurs. The <em>rebond</em> keyword will force a reset of the bond
list every <em>Nrebond</em> steps, even if an event has not occurred.
<em>Nrebond</em> must be a multiple of <em>Nevent</em>. This can be useful to check
if more frequent resets alter event statistics, perhaps because the
parameters chosen for defining what is a bond and what is an event are
producing bad dynamics in the presence of the bias potential.</p>
</section>
<hr class="docutils" />
<section id="restrictions">
<h2>Restrictions<a class="headerlink" href="#restrictions" title="Link to this heading"></a></h2>
<p>This command can only be used if LAMMPS was built with the REPLICA
package. See the <a class="reference internal" href="Build_package.html"><span class="doc">Build package</span></a> doc
page for more info.</p>
</section>
<section id="related-commands">
<h2>Related commands<a class="headerlink" href="#related-commands" title="Link to this heading"></a></h2>
<p><a class="reference internal" href="fix_hyper_global.html"><span class="doc">fix hyper/global</span></a>, <a class="reference internal" href="fix_hyper_local.html"><span class="doc">fix hyper/local</span></a>, <a class="reference internal" href="compute_event_displace.html"><span class="doc">compute event/displace</span></a>, <a class="reference internal" href="prd.html"><span class="doc">prd</span></a></p>
</section>
<section id="default">
<h2>Default<a class="headerlink" href="#default" title="Link to this heading"></a></h2>
<p>The option defaults are min = 0.1 0.1 40 50 and time = steps.</p>
<hr class="docutils" />
<p id="voter2013"><strong>(Voter2013)</strong> S. Y. Kim, D. Perez, A. F. Voter, J Chem Phys, 139,
144110 (2013).</p>
<p id="voter2002hd"><strong>(Voter2002)</strong> Voter, Montalenti, Germann, Annual Review of Materials
Research 32, 321 (2002).</p>
</section>
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