forked from lijiext/lammps
59 lines
1.3 KiB
Plaintext
59 lines
1.3 KiB
Plaintext
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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 charmm command :h3
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[Syntax:]
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angle_style charmm :pre
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[Examples:]
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angle_style charmm
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angle_coeff 1 300.0 107.0 50.0 3.0 :pre
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[Description:]
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The {charmm} angle style uses the potential
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:c,image(Eqs/angle_charmm.jpg)
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with an additional Urey_Bradley term based on the distance {r} between
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the 1st and 3rd atoms in the angle. K, theta0, Kub, and Rub are
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coefficients defined for each angle type.
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See "(MacKerell)"_#MacKerell for a description of the CHARMM force
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field.
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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)
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K_ub (energy/distance^2)
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r_ub (distance) :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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[Restrictions:] none
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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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:line
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:link(MacKerell)
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[(MacKerell)] MacKerell, Bashford, Bellott, Dunbrack, Evanseck, Field,
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Fischer, Gao, Guo, Ha, et al, J Phys Chem, 102, 3586 (1998).
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