lammps/doc/dipole.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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<H3>dipole command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>dipole I value
</PRE>
<UL><LI>I = atom type (see asterik form below)
<LI>value = dipole
</UL>
<P><B>Examples:</B>
</P>
<PRE>dipole 1 1.0
dipole 3 2.0
dipole 3*5 0.0
</PRE>
<P><B>Description:</B>
</P>
<P>Set the dipole moment for all atoms of one or more atom types. This
command is only used for atom styles that require dipole moments
(<A HREF = "atom_style.html">atom_style</A> dipole). A value of 0.0 should be used
if the atom type has no dipole moment. Dipole values can also be set
in the <A HREF = "read_data.html">read_data</A> data file. See the
<A HREF = "units.html">units</A> command for a discussion of dipole units.
</P>
<P>I can be specified in one of two ways. An explicit numeric value can
be used, as in the 1st example above. Or a wild-card asterik can be
used to set the dipole moment for multiple atom types. This takes the
form "*" or "*n" or "n*" or "m*n". If N = the number of atom types,
then an asterik with no numeric values means all types from 1 to N. A
leading asterik means all types from 1 to n (inclusive). A trailing
asterik means all types from n to N (inclusive). A middle asterik
means all types from m to n (inclusive).
</P>
<P>A line in a data file that specifies a dipole moement uses the exact
same format as the arguments of the dipole command in an input script,
except that no wild-card asterik can be used. For example, under the
"Dipoles" section of a data file, the line that corresponds to the 1st
example above would be listed as
</P>
<PRE>1 1.0
</PRE>
<P><B>Restrictions:</B>
</P>
<P>This command must come after the simulation box is defined by a
<A HREF = "read_data.html">read_data</A>, <A HREF = "read_restart.html">read_restart</A>, or
<A HREF = "create_box.html">create_box</A> command.
</P>
<P>All dipoles moments must be defined before a simulation is run (if the
atom style requires dipoles be set).
</P>
<P><B>Related commands:</B> none
</P>
<P><B>Default:</B> none
</P>
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