Page Menu
Home
c4science
Search
Configure Global Search
Log In
Files
F73445379
bond_hybrid.html
No One
Temporary
Actions
Download File
Edit File
Delete File
View Transforms
Subscribe
Mute Notifications
Award Token
Subscribers
None
File Metadata
Details
File Info
Storage
Attached
Created
Sun, Jul 21, 08:40
Size
2 KB
Mime Type
text/html
Expires
Tue, Jul 23, 08:40 (2 d)
Engine
blob
Format
Raw Data
Handle
19201194
Attached To
rLAMMPS lammps
bond_hybrid.html
View Options
<HTML>
<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>
</CENTER>
<HR>
<H3>bond_style hybrid command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>bond_style hybrid style1 style2 ...
</PRE>
<UL><LI>style1,style2 = list of one or more bond styles
</UL>
<P><B>Examples:</B>
</P>
<PRE>bond_style hybrid harmonic fene
bond_coeff 1 harmonic 80.0 1.2
bond_coeff 2* fene 30.0 1.5 1.0 1.0
</PRE>
<P><B>Description:</B>
</P>
<P>The <I>hybrid</I> style enables the use of multiple bond styles in one
simulation. A bond style is assigned to each bond type. For example,
bonds in a polymer flow (of bond type 1) could be computed with a
<I>fene</I> potential and bonds in the wall boundary (of bond type 2) could
be computed with a <I>harmonic</I> potential. The assignment of bond type
to style is made via the <A HREF = "bond_coeff.html">bond_coeff</A> command or in
the data file.
</P>
<P>In the bond_coeff commands, the name of a bond style must be added
after the bond type, with the remaining coefficients being those
appropriate to that style. In the example above, the 2 bond_coeff
commands set bonds of bond type 1 to be computed with a <I>harmonic</I>
potential with coefficients 80.0, 1.2 for K, r0. All other bond types
(2-N) are computed with a <I>fene</I> potential with coefficients 30.0,
1.5, 1.0, 1.0 for K, R0, epsilon, sigma.
</P>
<P>If bond coefficients are specified in the data file read via the
<A HREF = "read_data.html">read_data</A> command, then the same rule applies.
E.g. "harmonic" or "fene" must be added after the bond type, for each
line in the "Bond Coeffs" section, e.g.
</P>
<PRE>Bond Coeffs
</PRE>
<PRE>1 harmonic 80.0 1.2
2 fene 30.0 1.5 1.0 1.0
...
</PRE>
<P>A bond style of <I>none</I> with no additional coefficients can be used in
place of a bond style, either in a input script bond_coeff command or
in the data file, if you desire to turn off interactions for specific
bond types.
</P>
<HR>
<P><B>Restrictions:</B>
</P>
<P>This bond style can only be used if LAMMPS was built with the
MOLECULE package (which it is by default). See the <A HREF = "Section_start.html#start_3">Making
LAMMPS</A> section for more info on packages.
</P>
<P>Unlike other bond styles, the hybrid bond style does not store bond
coefficient info for individual sub-styles in a <A HREF = "restart.html">binary restart
files</A>. Thus when retarting a simulation from a restart
file, you need to re-specify bond_coeff commands.
</P>
<P><B>Related commands:</B>
</P>
<P><A HREF = "bond_coeff.html">bond_coeff</A>, <A HREF = "delete_bonds.html">delete_bonds</A>
</P>
<P><B>Default:</B> none
</P>
</HTML>
Event Timeline
Log In to Comment