2006-09-22 00:22:34 +08:00
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"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
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:link(lws,http://lammps.sandia.gov)
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:link(ld,Manual.html)
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:link(lc,Section_commands.html#comm)
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:line
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angle_style harmonic command :h3
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[Syntax:]
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angle_style harmonic :pre
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[Examples:]
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angle_style harmonic
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angle_coeff 1 300.0 107.0 :pre
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[Description:]
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The {harmonic} angle style uses the potential
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:c,image(Eqs/angle_harmonic.jpg)
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where theta0 is the equilibrium value of the angle, and K is a
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prefactor. Note that the usual 1/2 factor is included in K.
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The following coefficients must be defined for each angle type via the
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"angle_coeff"_angle_coeff.html command as in the example above, or in
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the data file or restart files read by the "read_data"_read_data.html
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or "read_restart"_read_restart.html commands:
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K (energy/radian^2)
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theta0 (degrees) :ul
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Theta0 is specified in degrees, but LAMMPS converts it to radians
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internally; hence the units of K are in energy/radian^2.
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2006-09-28 03:12:31 +08:00
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[Restrictions:] none
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2006-09-22 00:22:34 +08:00
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2007-06-26 08:03:39 +08:00
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This angle style can only be used if LAMMPS was built with the
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2011-08-27 02:53:00 +08:00
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MOLECULAR package (which it is by default). See the "Making
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2011-08-26 00:46:23 +08:00
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LAMMPS"_Section_start.html#start_3 section for more info on packages.
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2007-06-26 08:03:39 +08:00
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2006-09-22 00:22:34 +08:00
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[Related commands:]
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"angle_coeff"_angle_coeff.html
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[Default:] none
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