Page Menu
Home
c4science
Search
Configure Global Search
Log In
Files
F118769494
bond_fene_expand.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, Jun 22, 03:08
Size
2 KB
Mime Type
text/html
Expires
Tue, Jun 24, 03:08 (2 d)
Engine
blob
Format
Raw Data
Handle
26923589
Attached To
rLAMMPS lammps
bond_fene_expand.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 fene/expand command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>bond_style fene/expand
</PRE>
<P><B>Examples:</B>
</P>
<PRE>bond_style fene/expand
bond_coeff 1 30.0 1.5 1.0 1.0 0.5
</PRE>
<P><B>Description:</B>
</P>
<P>The <I>fene/expand</I> bond style uses the potential
</P>
<CENTER><IMG SRC = "Eqs/bond_fene_expand.jpg">
</CENTER>
<P>to define a finite extensible nonlinear elastic (FENE) potential
<A HREF = "#Kremer">(Kremer)</A>, used for bead-spring polymer models. The first
term is attractive, the 2nd Lennard-Jones term is repulsive.
</P>
<P>The <I>fene/expand</I> bond style is similar to <I>fene</I> except that an extra
shift factor of delta (positive or negative) is added to <I>r</I> to
effectively change the bead size of the bonded atoms. The first term
now extends to R0 + delta and the 2nd term is cutoff at 2^(1/6) sigma
+ delta.
</P>
<P>The following coefficients must be defined for each bond type via the
<A HREF = "bond_coeff.html">bond_coeff</A> command as in the example above, or in
the data file or restart files read by the <A HREF = "read_data.html">read_data</A>
or <A HREF = "read_restart.html">read_restart</A> commands:
</P>
<UL><LI>K (energy/distance^2)
<LI>R0 (distance)
<LI>epsilon (energy)
<LI>sigma (distance)
<LI>delta (distance)
</UL>
<P><B>Restrictions:</B>
</P>
<P>This bond style can only be used if LAMMPS was built with the
"molecular" package (which it is by default). See the <A HREF = "Section_start.html#2_3">Making
LAMMPS</A> section for more info on packages.
</P>
<P>You typically should specify <A HREF = "special_bonds.html">special_bonds 0 1 1</A>
to use this bond style. LAMMPS will issue a warning it that's not the
case.
</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>
<HR>
<A NAME = "Kremer"></A>
<P><B>(Kremer)</B> Kremer, Grest, J Chem Phys, 92, 5057 (1990).
</P>
</HTML>
Event Timeline
Log In to Comment