angle_cosine_squared.html
No OneTemporary
Actions

Subscribers

None

File Metadata

	<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>angle_style cosine/squared command
	</H3>
	<P><B>Syntax:</B>
	</P>
	<PRE>angle_style cosine/squared
	</PRE>
	<P><B>Examples:</B>
	</P>
	<PRE>angle_style cosine/squared
	angle_coeff 2*4 75.0 100.0
	</PRE>
	<P><B>Description:</B>
	</P>
	<P>The <I>cosine/squared</I> angle style uses the potential
	</P>
	<CENTER><IMG SRC = "Eqs/angle_cosine_squared.jpg">
	</CENTER>
	<P>where theta0 is the equilibrium value of the angle, and K is a
	prefactor. Note that the usual 1/2 factor is included in K.
	</P>
	<P>The following coefficients must be defined for each angle type via the
	<A HREF = "angle_coeff.html">angle_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)
	<LI>theta0 (degrees)
	</UL>
	<P>Theta0 is specified in degrees, but LAMMPS converts it to radians
	internally.
	</P>
	<P><B>Restrictions:</B>
	</P>
	<P>This angle 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><B>Related commands:</B>
	</P>
	<P><A HREF = "angle_coeff.html">angle_coeff</A>
	</P>
	<P><B>Default:</B> none
	</P>
	</HTML>