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			<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">
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			<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>
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