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<div class="section" id="compute-temp-drude-command">
<span id="index-0"></span><h1>compute temp/drude command</h1>
<div class="section" id="syntax">
<h2>Syntax</h2>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">compute</span> <span class="n">ID</span> <span class="n">group</span><span class="o">-</span><span class="n">ID</span> <span class="n">temp</span><span class="o">/</span><span class="n">drude</span>
</pre></div>
</div>
<ul class="simple">
<li>ID, group-ID are documented in <a class="reference internal" href="compute.html"><span class="doc">compute</span></a> command</li>
<li>temp/drude = style name of this compute command</li>
</ul>
</div>
<div class="section" id="examples">
<h2>Examples</h2>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="n">compute</span> <span class="n">TDRUDE</span> <span class="nb">all</span> <span class="n">temp</span><span class="o">/</span><span class="n">drude</span>
</pre></div>
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</div>
<div class="section" id="description">
<h2>Description</h2>
<p>Define a computation that calculates the temperatures of core-Drude
pairs. This compute is designed to be used with the
<a class="reference internal" href="tutorial_drude.html"><span class="doc">thermalized Drude oscillator model</span></a>. Polarizable
models in LAMMPS are described in <a class="reference internal" href="Section_howto.html#howto-25"><span class="std std-ref">this Section</span></a>.</p>
<p>Drude oscillators consist of a core particle and a Drude particle
connected by a harmonic bond, and the relative motion of these Drude
oscillators is usually maintained cold by a specific thermostat that
acts on the relative motion of the core-Drude particle
pairs. Therefore, because LAMMPS considers Drude particles as normal
atoms in its default temperature compute (<a class="reference internal" href="compute_temp.html"><span class="doc">compute temp</span></a> command), the reduced temperature of the
core-Drude particle pairs is not calculated correctly.</p>
<p>By contrast, this compute calculates the temperature of the cores
using center-of-mass velocities of the core-Drude pairs, and the
reduced temperature of the Drude particles using the relative
velocities of the Drude particles with respect to their cores.
Non-polarizable atoms are considered as cores. Their velocities
contribute to the temperature of the cores.</p>
<p><strong>Output info:</strong></p>
<p>This compute calculates a global scalar (the temperature) and a global
vector of length 6, which can be accessed by indices 1-6, whose components
are</p>
<ol class="arabic simple">
<li>temperature of the centers of mass (temperature units)</li>
<li>temperature of the dipoles (temperature units)</li>
<li>number of degrees of freedom of the centers of mass</li>
<li>number of degrees of freedom of the dipoles</li>
<li>kinetic energy of the centers of mass (energy units)</li>
<li>kinetic energy of the dipoles (energy units)</li>
</ol>
<p>These values can be used by any command that uses global scalar or
vector values from a compute as input. See <a class="reference internal" href="Section_howto.html#howto-15"><span class="std std-ref">this section</span></a> for an overview of LAMMPS output
options.</p>
<p>Both the scalar value and the first two values of the vector
calculated by this compute are &#8220;intensive&#8221;. The other 4 vector values
are &#8220;extensive&#8221;.</p>
</div>
<div class="section" id="restrictions">
<h2>Restrictions</h2>
<p>The number of degrees of freedom contributing to the temperature is
assumed to be constant for the duration of the run unless the
<em>fix_modify</em> command sets the option <em>dynamic yes</em>.</p>
</div>
<div class="section" id="related-commands">
<h2>Related commands</h2>
<p><a class="reference internal" href="fix_drude.html"><span class="doc">fix drude</span></a>, <a class="reference internal" href="fix_langevin_drude.html"><span class="doc">fix langevin/drude</span></a>, <a class="reference internal" href="fix_drude_transform.html"><span class="doc">fix drude/transform</span></a>, <a class="reference internal" href="pair_thole.html"><span class="doc">pair_style thole</span></a>, <a class="reference internal" href="compute_temp.html"><span class="doc">compute temp</span></a></p>
<p><strong>Default:</strong> none</p>
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