forked from lijiext/lammps
66 lines
2.3 KiB
HTML
66 lines
2.3 KiB
HTML
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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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</CENTER>
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<HR>
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<H3>create_atoms command
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</H3>
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<P><B>Syntax:</B>
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</P>
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<PRE>create_atoms type region-ID
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</PRE>
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<UL><LI>type = atom type (1-N) of atoms to create on a lattice
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<LI>region-ID = ID of region each atom will belong to (optional)
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</UL>
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<P><B>Examples:</B>
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</P>
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<PRE>create_atoms 1 regsphere
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create_atoms 3
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</PRE>
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<P><B>Description:</B>
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</P>
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<P>This command creates atoms on a lattice as an alternative to reading
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in their coordinates via a <A HREF = "read_data.html">read_data</A> or
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<A HREF = "read_restart.html">read_restart</A> command. A simulation box must
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already exist, which is created with the <A HREF = "create_box.html">create_box</A>
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command.
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</P>
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<P>Before using this command, a lattice must be defined using the
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<A HREF = "lattice.html">lattice</A> command. If a region is not specified, the
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create_atoms command fills the entire simulation box with atoms on the
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lattice. If a region is specified, then the geometric volume is
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filled that is inside the simulation box and is also consistent with
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the region volume.
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</P>
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<P>The <I>create_atoms</I> command can be used multiple times with different
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lattice orientations to create grain boundaries. Used in conjunction
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with the <A HREF = "delete_atoms.html">delete_atoms</A> command, reasonably complex
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geometries can be created. The <I>create_atoms</I> command can also be
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used to add atoms to a system previously read in from a data or
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restart file. In all these cases, care should be taken to insure that
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new atoms do not overlap existing atoms inappropriately.
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</P>
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<P>Created atoms are assigned the specified atom type and a velocity of
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0.0.
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</P>
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<P><B>Restrictions:</B>
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</P>
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<P>An <A HREF = "atom_style.html">atom_style</A> and <A HREF = "lattice.html">lattice</A> must be
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previously defined to use this command.
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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 = "lattice.html">lattice</A>, <A HREF = "orient.html">orient</A>, <A HREF = "origin.html">origin</A>,
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<A HREF = "region.html">region</A>, <A HREF = "create_box.html">create_box</A>,
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<A HREF = "read_data.html">read_data</A>, <A HREF = "read_restart.html">read_restart</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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