forked from lijiext/lammps
53 lines
1.4 KiB
Plaintext
53 lines
1.4 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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bond_style harmonic/shift/cut command :h3
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[Syntax:]
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bond_style harmonic/shift/cut :pre
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[Examples:]
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bond_style harmonic/shift/cut
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bond_coeff 5 10.0 0.5 1.0 :pre
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[Description:]
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The {harmonic/shift/cut} bond style is a shifted harmonic bond that
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uses the potential
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:c,image(Eqs/bond_harmonic_shift_cut.jpg)
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where r0 is the equilibrium bond distance, and rc the critical distance.
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The bond potential is zero for distances r > rc. The potential is -Umin
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at r0 and zero at rc. The spring constant is k = Umin / \[ 2 (r0-rc)^2\].
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The following coefficients must be defined for each bond type via the
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"bond_coeff"_bond_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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Umin (energy)
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r0 (distance)
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rc (distance) :ul
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[Restrictions:]
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This bond style can only be used if LAMMPS was built with the
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USER-MISC package. See the "Making LAMMPS"_Section_start.html#start_3
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section for more info on packages.
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[Related commands:]
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"bond_coeff"_bond_coeff.html, "delete_bonds"_delete_bonds.html,
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"bond_harmonic"_bond_harmonic.html,
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"bond_harmonicshift"_bond_harmonicshift.html
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[Default:] none
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