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<div class="section" id="pair-style-lj-cut-command">
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<span id="index-0"></span><h1>pair_style lj/cut command<a class="headerlink" href="#pair-style-lj-cut-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-cuda-command">
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<h1>pair_style lj/cut/cuda command<a class="headerlink" href="#pair-style-lj-cut-cuda-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-gpu-command">
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<h1>pair_style lj/cut/gpu command<a class="headerlink" href="#pair-style-lj-cut-gpu-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-intel-command">
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<h1>pair_style lj/cut/intel command<a class="headerlink" href="#pair-style-lj-cut-intel-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-kk-command">
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<h1>pair_style lj/cut/kk command<a class="headerlink" href="#pair-style-lj-cut-kk-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-opt-command">
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<h1>pair_style lj/cut/opt command<a class="headerlink" href="#pair-style-lj-cut-opt-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-omp-command">
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<h1>pair_style lj/cut/omp command<a class="headerlink" href="#pair-style-lj-cut-omp-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-cut-command">
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<h1>pair_style lj/cut/coul/cut command<a class="headerlink" href="#pair-style-lj-cut-coul-cut-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-cut-cuda-command">
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<h1>pair_style lj/cut/coul/cut/cuda command<a class="headerlink" href="#pair-style-lj-cut-coul-cut-cuda-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-cut-gpu-command">
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<h1>pair_style lj/cut/coul/cut/gpu command<a class="headerlink" href="#pair-style-lj-cut-coul-cut-gpu-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-cut-omp-command">
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<h1>pair_style lj/cut/coul/cut/omp command<a class="headerlink" href="#pair-style-lj-cut-coul-cut-omp-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-debye-command">
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<h1>pair_style lj/cut/coul/debye command<a class="headerlink" href="#pair-style-lj-cut-coul-debye-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-debye-cuda-command">
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<h1>pair_style lj/cut/coul/debye/cuda command<a class="headerlink" href="#pair-style-lj-cut-coul-debye-cuda-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-debye-gpu-command">
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<h1>pair_style lj/cut/coul/debye/gpu command<a class="headerlink" href="#pair-style-lj-cut-coul-debye-gpu-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-debye-kk-command">
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<h1>pair_style lj/cut/coul/debye/kk command<a class="headerlink" href="#pair-style-lj-cut-coul-debye-kk-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-debye-omp-command">
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<h1>pair_style lj/cut/coul/debye/omp command<a class="headerlink" href="#pair-style-lj-cut-coul-debye-omp-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-dsf-command">
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<h1>pair_style lj/cut/coul/dsf command<a class="headerlink" href="#pair-style-lj-cut-coul-dsf-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-dsf-gpu-command">
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<h1>pair_style lj/cut/coul/dsf/gpu command<a class="headerlink" href="#pair-style-lj-cut-coul-dsf-gpu-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-dsf-kk-command">
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<h1>pair_style lj/cut/coul/dsf/kk command<a class="headerlink" href="#pair-style-lj-cut-coul-dsf-kk-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-dsf-omp-command">
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<h1>pair_style lj/cut/coul/dsf/omp command<a class="headerlink" href="#pair-style-lj-cut-coul-dsf-omp-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-long-command">
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<h1>pair_style lj/cut/coul/long command<a class="headerlink" href="#pair-style-lj-cut-coul-long-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-long-cs-command">
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<h1>pair_style lj/cut/coul/long/cs command<a class="headerlink" href="#pair-style-lj-cut-coul-long-cs-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-long-cuda-command">
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<h1>pair_style lj/cut/coul/long/cuda command<a class="headerlink" href="#pair-style-lj-cut-coul-long-cuda-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-long-gpu-command">
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<h1>pair_style lj/cut/coul/long/gpu command<a class="headerlink" href="#pair-style-lj-cut-coul-long-gpu-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-long-intel-command">
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<h1>pair_style lj/cut/coul/long/intel command<a class="headerlink" href="#pair-style-lj-cut-coul-long-intel-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-long-opt-command">
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<h1>pair_style lj/cut/coul/long/opt command<a class="headerlink" href="#pair-style-lj-cut-coul-long-opt-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-long-omp-command">
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<h1>pair_style lj/cut/coul/long/omp command<a class="headerlink" href="#pair-style-lj-cut-coul-long-omp-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-msm-command">
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<h1>pair_style lj/cut/coul/msm command<a class="headerlink" href="#pair-style-lj-cut-coul-msm-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-msm-gpu-command">
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<h1>pair_style lj/cut/coul/msm/gpu command<a class="headerlink" href="#pair-style-lj-cut-coul-msm-gpu-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-coul-msm-omp-command">
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<h1>pair_style lj/cut/coul/msm/omp command<a class="headerlink" href="#pair-style-lj-cut-coul-msm-omp-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-tip4p-cut-command">
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<h1>pair_style lj/cut/tip4p/cut command<a class="headerlink" href="#pair-style-lj-cut-tip4p-cut-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-tip4p-cut-omp-command">
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<h1>pair_style lj/cut/tip4p/cut/omp command<a class="headerlink" href="#pair-style-lj-cut-tip4p-cut-omp-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-tip4p-long-command">
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<h1>pair_style lj/cut/tip4p/long command<a class="headerlink" href="#pair-style-lj-cut-tip4p-long-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-tip4p-long-omp-command">
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<h1>pair_style lj/cut/tip4p/long/omp command<a class="headerlink" href="#pair-style-lj-cut-tip4p-long-omp-command" title="Permalink to this headline">¶</a></h1>
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</div>
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<div class="section" id="pair-style-lj-cut-tip4p-long-opt-command">
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<h1>pair_style lj/cut/tip4p/long/opt command<a class="headerlink" href="#pair-style-lj-cut-tip4p-long-opt-command" title="Permalink to this headline">¶</a></h1>
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<div class="section" id="syntax">
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<h2>Syntax<a class="headerlink" href="#syntax" title="Permalink to this headline">¶</a></h2>
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<div class="highlight-python"><div class="highlight"><pre>pair_style style args
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</pre></div>
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</div>
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<ul class="simple">
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<li>style = <em>lj/cut</em> or <em>lj/cut/coul/cut</em> or <em>lj/cut/coul/debye</em> or <em>lj/cut/coul/dsf</em> or <em>lj/cut/coul/long</em> or <em>lj/cut/coul/long/cs</em> or <em>lj/cut/coul/msm</em> or <em>lj/cut/tip4p/long</em></li>
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<li>args = list of arguments for a particular style</li>
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</ul>
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<pre class="literal-block">
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<em>lj/cut</em> args = cutoff
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cutoff = global cutoff for Lennard Jones interactions (distance units)
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<em>lj/cut/coul/cut</em> args = cutoff (cutoff2)
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cutoff = global cutoff for LJ (and Coulombic if only 1 arg) (distance units)
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cutoff2 = global cutoff for Coulombic (optional) (distance units)
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<em>lj/cut/coul/debye</em> args = kappa cutoff (cutoff2)
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kappa = inverse of the Debye length (inverse distance units)
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cutoff = global cutoff for LJ (and Coulombic if only 1 arg) (distance units)
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cutoff2 = global cutoff for Coulombic (optional) (distance units)
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<em>lj/cut/coul/dsf</em> args = alpha cutoff (cutoff2)
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alpha = damping parameter (inverse distance units)
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cutoff = global cutoff for LJ (and Coulombic if only 1 arg) (distance units)
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cutoff2 = global cutoff for Coulombic (distance units)
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<em>lj/cut/coul/long</em> args = cutoff (cutoff2)
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cutoff = global cutoff for LJ (and Coulombic if only 1 arg) (distance units)
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cutoff2 = global cutoff for Coulombic (optional) (distance units)
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<em>lj/cut/coul/msm</em> args = cutoff (cutoff2)
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cutoff = global cutoff for LJ (and Coulombic if only 1 arg) (distance units)
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cutoff2 = global cutoff for Coulombic (optional) (distance units)
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<em>lj/cut/tip4p/cut</em> args = otype htype btype atype qdist cutoff (cutoff2)
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otype,htype = atom types for TIP4P O and H
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btype,atype = bond and angle types for TIP4P waters
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qdist = distance from O atom to massless charge (distance units)
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cutoff = global cutoff for LJ (and Coulombic if only 1 arg) (distance units)
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cutoff2 = global cutoff for Coulombic (optional) (distance units)
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<em>lj/cut/tip4p/long</em> args = otype htype btype atype qdist cutoff (cutoff2)
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otype,htype = atom types for TIP4P O and H
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btype,atype = bond and angle types for TIP4P waters
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qdist = distance from O atom to massless charge (distance units)
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cutoff = global cutoff for LJ (and Coulombic if only 1 arg) (distance units)
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cutoff2 = global cutoff for Coulombic (optional) (distance units)
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</pre>
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</div>
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<div class="section" id="examples">
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<h2>Examples<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h2>
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<div class="highlight-python"><div class="highlight"><pre>pair_style lj/cut 2.5
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pair_coeff * * 1 1
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pair_coeff 1 1 1 1.1 2.8
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</pre></div>
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</div>
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<div class="highlight-python"><div class="highlight"><pre>pair_style lj/cut/coul/cut 10.0
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pair_style lj/cut/coul/cut 10.0 8.0
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pair_coeff * * 100.0 3.0
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pair_coeff 1 1 100.0 3.5 9.0
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pair_coeff 1 1 100.0 3.5 9.0 9.0
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</pre></div>
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</div>
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<div class="highlight-python"><div class="highlight"><pre>pair_style lj/cut/coul/debye 1.5 3.0
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pair_style lj/cut/coul/debye 1.5 2.5 5.0
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pair_coeff * * 1.0 1.0
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pair_coeff 1 1 1.0 1.5 2.5
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pair_coeff 1 1 1.0 1.5 2.5 5.0
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</pre></div>
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</div>
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<div class="highlight-python"><div class="highlight"><pre>pair_style lj/cut/coul/dsf 0.05 2.5 10.0
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pair_coeff * * 1.0 1.0
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pair_coeff 1 1 1.0 1.0 2.5
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</pre></div>
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</div>
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<div class="highlight-python"><div class="highlight"><pre>pair_style lj/cut/coul/long 10.0
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pair_style lj/cut/coul/long/cs 10.0
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pair_style lj/cut/coul/long 10.0 8.0
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pair_style lj/cut/coul/long/cs 10.0 8.0
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pair_coeff * * 100.0 3.0
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pair_coeff 1 1 100.0 3.5 9.0
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</pre></div>
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</div>
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<div class="highlight-python"><div class="highlight"><pre>pair_style lj/cut/coul/msm 10.0
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pair_style lj/cut/coul/msm 10.0 8.0
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pair_coeff * * 100.0 3.0
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pair_coeff 1 1 100.0 3.5 9.0
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</pre></div>
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</div>
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<div class="highlight-python"><div class="highlight"><pre>pair_style lj/cut/tip4p/cut 1 2 7 8 0.15 12.0
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pair_style lj/cut/tip4p/cut 1 2 7 8 0.15 12.0 10.0
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pair_coeff * * 100.0 3.0
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pair_coeff 1 1 100.0 3.5 9.0
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</pre></div>
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</div>
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<div class="highlight-python"><div class="highlight"><pre>pair_style lj/cut/tip4p/long 1 2 7 8 0.15 12.0
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pair_style lj/cut/tip4p/long 1 2 7 8 0.15 12.0 10.0
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pair_coeff * * 100.0 3.0
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pair_coeff 1 1 100.0 3.5 9.0
|
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</pre></div>
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</div>
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</div>
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<div class="section" id="description">
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<h2>Description<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2>
|
|
<p>The <em>lj/cut</em> styles compute the standard 12/6 Lennard-Jones potential,
|
|
given by</p>
|
|
<img alt="_images/pair_lj.jpg" class="align-center" src="_images/pair_lj.jpg" />
|
|
<p>Rc is the cutoff.</p>
|
|
<p>Style <em>lj/cut/coul/cut</em> adds a Coulombic pairwise interaction given by</p>
|
|
<img alt="_images/pair_coulomb.jpg" class="align-center" src="_images/pair_coulomb.jpg" />
|
|
<p>where C is an energy-conversion constant, Qi and Qj are the charges on
|
|
the 2 atoms, and epsilon is the dielectric constant which can be set
|
|
by the <a class="reference internal" href="dielectric.html"><em>dielectric</em></a> command. If one cutoff is
|
|
specified in the pair_style command, it is used for both the LJ and
|
|
Coulombic terms. If two cutoffs are specified, they are used as
|
|
cutoffs for the LJ and Coulombic terms respectively.</p>
|
|
<p>Style <em>lj/cut/coul/debye</em> adds an additional exp() damping factor
|
|
to the Coulombic term, given by</p>
|
|
<img alt="_images/pair_debye.jpg" class="align-center" src="_images/pair_debye.jpg" />
|
|
<p>where kappa is the inverse of the Debye length. This potential is
|
|
another way to mimic the screening effect of a polar solvent.</p>
|
|
<p>Style <em>lj/cut/coul/dsf</em> computes the Coulombic term via the damped
|
|
shifted force model described in <a class="reference internal" href="#fennell"><span>Fennell</span></a>, given by:</p>
|
|
<img alt="_images/pair_coul_dsf.jpg" class="align-center" src="_images/pair_coul_dsf.jpg" />
|
|
<p>where <em>alpha</em> is the damping parameter and erfc() is the complementary
|
|
error-function. This potential is essentially a short-range,
|
|
spherically-truncated, charge-neutralized, shifted, pairwise <em>1/r</em>
|
|
summation. The potential is based on Wolf summation, proposed as an
|
|
alternative to Ewald summation for condensed phase systems where
|
|
charge screening causes electrostatic interactions to become
|
|
effectively short-ranged. In order for the electrostatic sum to be
|
|
absolutely convergent, charge neutralization within the cutoff radius
|
|
is enforced by shifting the potential through placement of image
|
|
charges on the cutoff sphere. Convergence can often be improved by
|
|
setting <em>alpha</em> to a small non-zero value.</p>
|
|
<p>Styles <em>lj/cut/coul/long</em> and <em>lj/cut/coul/msm</em> compute the same
|
|
Coulombic interactions as style <em>lj/cut/coul/cut</em> except that an
|
|
additional damping factor is applied to the Coulombic term so it can
|
|
be used in conjunction with the <a class="reference internal" href="kspace_style.html"><em>kspace_style</em></a>
|
|
command and its <em>ewald</em> or <em>pppm</em> option. The Coulombic cutoff
|
|
specified for this style means that pairwise interactions within this
|
|
distance are computed directly; interactions outside that distance are
|
|
computed in reciprocal space.</p>
|
|
<p>Style <em>lj/cut/coul/long/cs</em> is identical to <em>lj/cut/coul/long</em> except
|
|
that a term is added for the <a class="reference internal" href="Section_howto.html#howto-25"><span>core/shell model</span></a> to allow charges on core and shell
|
|
particles to be separated by r = 0.0.</p>
|
|
<p>Styles <em>lj/cut/tip4p/cut</em> and <em>lj/cut/tip4p/long</em> implement the TIP4P
|
|
water model of <a class="reference internal" href="#jorgensen"><span>(Jorgensen)</span></a>, which introduces a massless
|
|
site located a short distance away from the oxygen atom along the
|
|
bisector of the HOH angle. The atomic types of the oxygen and
|
|
hydrogen atoms, the bond and angle types for OH and HOH interactions,
|
|
and the distance to the massless charge site are specified as
|
|
pair_style arguments. Style <em>lj/cut/tip4p/cut</em> uses a cutoff for
|
|
Coulomb interactions; style <em>lj/cut/tip4p/long</em> is for use with a
|
|
long-range Coulombic solver (Ewald or PPPM).</p>
|
|
<div class="admonition note">
|
|
<p class="first admonition-title">Note</p>
|
|
<p class="last">For each TIP4P water molecule in your system, the atom IDs for
|
|
the O and 2 H atoms must be consecutive, with the O atom first. This
|
|
is to enable LAMMPS to “find” the 2 H atoms associated with each O
|
|
atom. For example, if the atom ID of an O atom in a TIP4P water
|
|
molecule is 500, then its 2 H atoms must have IDs 501 and 502.</p>
|
|
</div>
|
|
<p>See the <a class="reference internal" href="Section_howto.html#howto-8"><span>howto section</span></a> for more
|
|
information on how to use the TIP4P pair styles and lists of
|
|
parameters to set. Note that the neighobr list cutoff for Coulomb
|
|
interactions is effectively extended by a distance 2*qdist when using
|
|
the TIP4P pair style, to account for the offset distance of the
|
|
fictitious charges on O atoms in water molecules. Thus it is
|
|
typically best in an efficiency sense to use a LJ cutoff >= Coulomb
|
|
cutoff + 2*qdist, to shrink the size of the neighbor list. This leads
|
|
to slightly larger cost for the long-range calculation, so you can
|
|
test the trade-off for your model.</p>
|
|
<p>For all of the <em>lj/cut</em> pair styles, the following coefficients must
|
|
be defined for each pair of atoms types via the
|
|
<a class="reference internal" href="pair_coeff.html"><em>pair_coeff</em></a> command as in the examples above, or in
|
|
the data file or restart files read by the <a class="reference internal" href="read_data.html"><em>read_data</em></a>
|
|
or <a class="reference internal" href="read_restart.html"><em>read_restart</em></a> commands, or by mixing as
|
|
described below:</p>
|
|
<ul class="simple">
|
|
<li>epsilon (energy units)</li>
|
|
<li>sigma (distance units)</li>
|
|
<li>cutoff1 (distance units)</li>
|
|
<li>cutoff2 (distance units)</li>
|
|
</ul>
|
|
<p>Note that sigma is defined in the LJ formula as the zero-crossing
|
|
distance for the potential, not as the energy minimum at 2^(1/6)
|
|
sigma.</p>
|
|
<p>The latter 2 coefficients are optional. If not specified, the global
|
|
LJ and Coulombic cutoffs specified in the pair_style command are used.
|
|
If only one cutoff is specified, it is used as the cutoff for both LJ
|
|
and Coulombic interactions for this type pair. If both coefficients
|
|
are specified, they are used as the LJ and Coulombic cutoffs for this
|
|
type pair. You cannot specify 2 cutoffs for style <em>lj/cut</em>, since it
|
|
has no Coulombic terms.</p>
|
|
<p>For <em>lj/cut/coul/long</em> and <em>lj/cut/coul/msm</em> and <em>lj/cut/tip4p/cut</em>
|
|
and <em>lj/cut/tip4p/long</em> only the LJ cutoff can be specified since a
|
|
Coulombic cutoff cannot be specified for an individual I,J type pair.
|
|
All type pairs use the same global Coulombic cutoff specified in the
|
|
pair_style command.</p>
|
|
<hr class="docutils" />
|
|
<p>Styles with a <em>cuda</em>, <em>gpu</em>, <em>intel</em>, <em>kk</em>, <em>omp</em>, or <em>opt</em> suffix are
|
|
functionally the same as the corresponding style without the suffix.
|
|
They have been optimized to run faster, depending on your available
|
|
hardware, as discussed in <a class="reference internal" href="Section_accelerate.html"><em>Section_accelerate</em></a>
|
|
of the manual. The accelerated styles take the same arguments and
|
|
should produce the same results, except for round-off and precision
|
|
issues.</p>
|
|
<p>These accelerated styles are part of the USER-CUDA, GPU, USER-INTEL,
|
|
KOKKOS, USER-OMP and OPT packages, respectively. They are only
|
|
enabled if LAMMPS was built with those packages. See the <a class="reference internal" href="Section_start.html#start-3"><span>Making LAMMPS</span></a> section for more info.</p>
|
|
<p>You can specify the accelerated styles explicitly in your input script
|
|
by including their suffix, or you can use the <a class="reference internal" href="Section_start.html#start-7"><span>-suffix command-line switch</span></a> when you invoke LAMMPS, or you can
|
|
use the <a class="reference internal" href="suffix.html"><em>suffix</em></a> command in your input script.</p>
|
|
<p>See <a class="reference internal" href="Section_accelerate.html"><em>Section_accelerate</em></a> of the manual for
|
|
more instructions on how to use the accelerated styles effectively.</p>
|
|
<hr class="docutils" />
|
|
<p><strong>Mixing, shift, table, tail correction, restart, rRESPA info</strong>:</p>
|
|
<p>For atom type pairs I,J and I != J, the epsilon and sigma coefficients
|
|
and cutoff distance for all of the lj/cut pair styles can be mixed.
|
|
The default mix value is <em>geometric</em>. See the “pair_modify” command
|
|
for details.</p>
|
|
<p>All of the <em>lj/cut</em> pair styles support the
|
|
<a class="reference internal" href="pair_modify.html"><em>pair_modify</em></a> shift option for the energy of the
|
|
Lennard-Jones portion of the pair interaction.</p>
|
|
<p>The <em>lj/cut/coul/long</em> and <em>lj/cut/tip4p/long</em> pair styles support the
|
|
<a class="reference internal" href="pair_modify.html"><em>pair_modify</em></a> table option since they can tabulate
|
|
the short-range portion of the long-range Coulombic interaction.</p>
|
|
<p>All of the <em>lj/cut</em> pair styles support the
|
|
<a class="reference internal" href="pair_modify.html"><em>pair_modify</em></a> tail option for adding a long-range
|
|
tail correction to the energy and pressure for the Lennard-Jones
|
|
portion of the pair interaction.</p>
|
|
<p>All of the <em>lj/cut</em> pair styles write their information to <a class="reference internal" href="restart.html"><em>binary restart files</em></a>, so pair_style and pair_coeff commands do
|
|
not need to be specified in an input script that reads a restart file.</p>
|
|
<p>The <em>lj/cut</em> and <em>lj/cut/coul/long</em> pair styles support the use of the
|
|
<em>inner</em>, <em>middle</em>, and <em>outer</em> keywords of the <a class="reference internal" href="run_style.html"><em>run_style respa</em></a> command, meaning the pairwise forces can be
|
|
partitioned by distance at different levels of the rRESPA hierarchy.
|
|
The other styles only support the <em>pair</em> keyword of run_style respa.
|
|
See the <a class="reference internal" href="run_style.html"><em>run_style</em></a> command for details.</p>
|
|
</div>
|
|
<hr class="docutils" />
|
|
<div class="section" id="restrictions">
|
|
<h2>Restrictions<a class="headerlink" href="#restrictions" title="Permalink to this headline">¶</a></h2>
|
|
<p>The <em>lj/cut/coul/long</em> and <em>lj/cut/tip4p/long</em> styles are part of the
|
|
KSPACE package. The <em>lj/cut/tip4p/cut</em> style is part of the MOLECULE
|
|
package. These styles are only enabled if LAMMPS was built with those
|
|
packages. See the <a class="reference internal" href="Section_start.html#start-3"><span>Making LAMMPS</span></a> section
|
|
for more info. Note that the KSPACE and MOLECULE packages are
|
|
installed by default.</p>
|
|
</div>
|
|
<div class="section" id="related-commands">
|
|
<h2>Related commands<a class="headerlink" href="#related-commands" title="Permalink to this headline">¶</a></h2>
|
|
<p><a class="reference internal" href="pair_coeff.html"><em>pair_coeff</em></a></p>
|
|
<p><strong>Default:</strong> none</p>
|
|
<hr class="docutils" />
|
|
<p id="jorgensen"><strong>(Jorgensen)</strong> Jorgensen, Chandrasekhar, Madura, Impey, Klein, J Chem
|
|
Phys, 79, 926 (1983).</p>
|
|
<p id="fennell"><strong>(Fennell)</strong> C. J. Fennell, J. D. Gezelter, J Chem Phys, 124,
|
|
234104 (2006).</p>
|
|
</div>
|
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