forked from lijiext/lammps
76 lines
2.3 KiB
Plaintext
76 lines
2.3 KiB
Plaintext
"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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angle_style harmonic/omp 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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:line
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Styles with a {cuda}, {gpu}, {omp}, or {opt} suffix are functionally
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the same as the corresponding style without the suffix. They have
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been optimized to run faster, depending on your available hardware, as
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discussed in "Section_accelerate"_Section_accelerate.html of the
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manual. The accelerated styles take the same arguments and should
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produce the same results, except for round-off and precision issues.
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These accelerated styles are part of the USER-CUDA, GPU, USER-OMP and OPT
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packages, respectively. They are only enabled if LAMMPS was built with
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those packages. See the "Making LAMMPS"_Section_start.html#start_3
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section for more info.
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You can specify the accelerated styles explicitly in your input script
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by including their suffix, or you can use the "-suffix command-line
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switch"_Section_start.html#start_7 when you invoke LAMMPS, or you can
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use the "suffix"_suffix.html command in your input script.
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See "Section_accelerate"_Section_accelerate.html of the manual for
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more instructions on how to use the accelerated styles effectively.
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:line
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[Restrictions:] none
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This angle style can only be used if LAMMPS was built with the
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MOLECULAR package (which it is by default). See the "Making
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LAMMPS"_Section_start.html#start_3 section for more info on packages.
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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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