forked from lijiext/lammps
55 lines
1.3 KiB
Plaintext
55 lines
1.3 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,Commands_all.html)
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:line
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improper_style sqdistharm command :h3
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[Syntax:]
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improper_style sqdistharm
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[Examples:]
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improper_style sqdistharm
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improper_coeff 1 50.0 0.1 :pre
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[Description:]
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The {sqdistharm} improper style uses the potential
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:c,image(Eqs/improper_sqdistharm.jpg)
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where d is the distance between the central atom and the plane formed
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by the other three atoms. If the 4 atoms in an improper quadruplet
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(listed in the data file read by the "read_data"_read_data.html
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command) are ordered I,J,K,L then the L-atom is assumed to be the
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central atom. Note that this is different from the convention used
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in the improper_style distance.
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The following coefficients must be defined for each improper type via
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the improper_coeff command as in the example above, or in the data
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file or restart files read by the read_data or read_restart commands:
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K (energy/distance^4)
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d0^2 (distance^2) :ul
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Note that d0^2 (in units distance^2) has be provided and not d0.
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:line
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[Restrictions:]
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This improper style can only be used if LAMMPS was built with the
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USER-MISC package. See the "Build package"_Build_package.html doc
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page for more info.
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[Related commands:]
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"improper_coeff"_improper_coeff.html
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[Default:] none
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