2009-08-11 04:13:44 +08:00
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<CENTER><A HREF = "http://lammps.sandia.gov">LAMMPS WWW Site</A> - <A HREF = "Manual.html">LAMMPS Documentation</A> - <A HREF = "Section_commands.html#comm">LAMMPS Commands</A>
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<H3>pair_style lj96/cut command
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</H3>
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2011-06-09 05:46:03 +08:00
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<H3>pair_style lj96/cut/cuda command
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</H3>
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2010-11-23 08:51:42 +08:00
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<H3>pair_style lj96/cut/gpu command
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</H3>
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2009-08-11 04:13:44 +08:00
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<P><B>Syntax:</B>
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</P>
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2011-06-09 05:26:06 +08:00
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<PRE>pair_style lj96/cut cutoff
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2009-08-11 04:13:44 +08:00
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</PRE>
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2011-06-09 05:26:06 +08:00
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<UL><LI>cutoff = global cutoff for lj96/cut interactions (distance units)
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2009-08-11 04:13:44 +08:00
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</UL>
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<P><B>Examples:</B>
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</P>
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<PRE>pair_style lj96/cut 2.5
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2010-05-15 00:14:47 +08:00
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pair_coeff * * 1.0 1.0 4.0
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pair_coeff 1 1 1.0 1.0
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2009-08-11 04:13:44 +08:00
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</PRE>
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<P><B>Description:</B>
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</P>
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<P>The <I>lj96/cut</I> style compute a 9/6 Lennard-Jones potential, instead
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of the standard 12/6 potential, given by
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</P>
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<CENTER><IMG SRC = "Eqs/pair_lj96.jpg">
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</CENTER>
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<P>Rc is the cutoff.
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</P>
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<P>The following coefficients must be defined for each pair of atoms
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types via the <A HREF = "pair_coeff.html">pair_coeff</A> command as in the examples
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above, or in the data file or restart files read by the
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<A HREF = "read_data.html">read_data</A> or <A HREF = "read_restart.html">read_restart</A>
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commands, or by mixing as described below:
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</P>
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<UL><LI>epsilon (energy units)
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<LI>sigma (distance units)
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<LI>cutoff (distance units)
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</UL>
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<P>The last coefficient is optional. If not specified, the global LJ
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cutoff specified in the pair_style command is used.
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</P>
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<HR>
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2011-06-09 05:26:06 +08:00
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<P>Styles with a <I>cuda</I>, <I>gpu</I>, or <I>opt</I> suffix are functionally the same
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as the corresponding style without the suffix. They have been
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optimized to run faster, depending on your available hardware, as
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discussed in <A HREF = "Section_accelerate.html">this section</A> of the manual.
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The accelerated styles take the same arguments and should produce the
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same results, except for round-off and precision issues.
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</P>
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2011-08-27 02:53:00 +08:00
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<P>These accelerated styles are part of the USER-CUDA, GPU, and OPT
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2011-06-09 05:26:06 +08:00
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packages respectively. They are only enabled if LAMMPS was built with
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2011-08-26 00:46:23 +08:00
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those packages. See the <A HREF = "Section_start.html#start_3">Making LAMMPS</A>
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2011-06-09 05:26:06 +08:00
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section for more info.
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</P>
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<P>You can specify the accelerated styles explicitly in your input script
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2011-08-26 00:46:23 +08:00
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by including their suffix, or you can use the <A HREF = "Section_start.html#start_6">-suffix command-line
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switch</A> when you invoke LAMMPS, or you can
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use the <A HREF = "suffix.html">suffix</A> command in your input script.
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2011-06-09 05:26:06 +08:00
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</P>
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<P>See <A HREF = "Section_accelerate.html">this section</A> of the manual for more
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instructions on how to use the accelerated styles effectively.
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2010-11-23 08:51:42 +08:00
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</P>
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<HR>
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2009-08-11 04:13:44 +08:00
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<P><B>Mixing, shift, table, tail correction, restart, rRESPA info</B>:
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</P>
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<P>For atom type pairs I,J and I != J, the epsilon and sigma coefficients
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and cutoff distance for all of the lj/cut pair styles can be mixed.
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The default mix value is <I>geometric</I>. See the "pair_modify" command
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for details.
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</P>
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<P>This pair style supports the <A HREF = "pair_modify.html">pair_modify</A> shift
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option for the energy of the pair interaction.
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</P>
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<P>The <A HREF = "pair_modify.html">pair_modify</A> table option is not relevant
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for this pair style.
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</P>
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<P>This pair style supports the <A HREF = "pair_modify.html">pair_modify</A> tail
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option for adding a long-range tail correction to the energy and
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pressure of the pair interaction.
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</P>
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<P>This pair style writes its information to <A HREF = "restart.html">binary restart
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files</A>, so pair_style and pair_coeff commands do not need
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to be specified in an input script that reads a restart file.
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</P>
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<P>This pair style supports the use of the <I>inner</I>, <I>middle</I>, and <I>outer</I>
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keywords of the <A HREF = "run_style.html">run_style respa</A> command, meaning the
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pairwise forces can be partitioned by distance at different levels of
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the rRESPA hierarchy. See the <A HREF = "run_style.html">run_style</A> command for
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details.
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</P>
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<HR>
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2011-06-09 05:26:06 +08:00
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<P><B>Restrictions:</B> none
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2009-08-11 04:13:44 +08:00
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</P>
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<P><B>Related commands:</B>
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</P>
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<P><A HREF = "pair_coeff.html">pair_coeff</A>
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</P>
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<P><B>Default:</B> none
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</P>
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</HTML>
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