Merge pull request #417 from tonnamb/add-pair-zhou

add new pair potential for metal-organic interactions - pair style momb

doc/src/Eqs/pair_momb.tex

@@ -0,0 +1,13 @@
+\documentclass[12pt,fleqn]{article}
+\usepackage{amsmath}
+\thispagestyle{empty}
+
+\begin{document}
+
+\setlength{\jot}{2ex}
+\begin{gather*}
+  E = D_0 [\exp^{-2 \alpha (r-r_0)} - 2\exp^{-\alpha (r-r_0)}] - s_6 \frac{C_6}{r^6} f_{damp}(r,R_r) \\
+  f_{damp}(r,R_r) = \frac{1}{1 + \exp^{-d(r/R_r - 1)}}
+\end{gather*}
+
+\end{document}

doc/src/Section_commands.txt

@@ -1035,6 +1035,7 @@ package"_Section_start.html#start_3.
 "meam/spline (o)"_pair_meam_spline.html,
 "meam/sw/spline"_pair_meam_sw_spline.html,
 "mgpt"_pair_mgpt.html,
+"momb"_pair_momb.html,
 "morse/smooth/linear"_pair_morse.html,
 "morse/soft"_pair_morse.html,
 "multi/lucy"_pair_multi_lucy.html,
@@ -1061,7 +1062,7 @@ package"_Section_start.html#start_3.
 "table/rx"_pair_table_rx.html,
 "tersoff/table (o)"_pair_tersoff.html,
 "thole"_pair_thole.html,
-"tip4p/long/soft (o)"_pair_lj_soft.html :tb(c=4,ea=c)
+"tip4p/long/soft (o)"_pair_lj_soft.html :tb(c=4,ea=c) 
 
 :line
 

doc/src/lammps.book

@@ -456,6 +456,7 @@ pair_meam_spline.html
 pair_meam_sw_spline.html
 pair_mgpt.html
 pair_mie.html
+pair_momb.html
 pair_morse.html
 pair_multi_lucy.html
 pair_multi_lucy_rx.html

doc/src/pair_momb.txt

@@ -0,0 +1,70 @@
+"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
+
+:link(lws,http://lammps.sandia.gov)
+:link(ld,Manual.html)
+:link(lc,Section_commands.html#comm)
+
+:line
+
+pair_style momb command :h3
+
+[Syntax:]
+
+pair_style momb cutoff s6 d :pre
+
+cutoff = global cutoff (distance units)
+s6 = global scaling factor of the exchange-correlation functional used (unitless)
+d = damping scaling factor of Grimme's method (unitless) :ul
+
+[Examples:]
+
+pair_style momb 12.0 0.75 20.0
+pair_style hybrid/overlay eam/fs lj/charmm/coul/long 10.0 12.0 momb 12.0 0.75 20.0 morse 5.5 :pre
+
+pair_coeff 1 2 momb 0.0 1.0 1.0 10.2847 2.361 :pre
+
+[Description:]
+
+Style {momb} computes pairwise van der Waals (vdW) and short-range interactions using the
+Morse potential and "(Grimme)"_#Grimme method implemented in the Many-Body
+Metal-Organic (MOMB) force field described comprehensively in "(Fichthorn)"_#Fichthorn and
+"(Zhou)"_#Zhou4. Grimme's method is widely used to correct for dispersion
+in density functional theory calculations.
+
+:c,image(Eqs/pair_momb.jpg)
+
+For the {momb} pair style, the following coefficients must be defined for each
+pair of atoms types via the "pair_coeff"_pair_coeff.html command as in the
+examples above, or in the data file or restart files read by the 
+"read_data"_read_data.html as described below:
+
+D0 (energy units)
+alpha (1/distance units)
+r0 (distance units)
+C6 (energy*distance^6 units)
+Rr (distance units, typically sum of atomic vdW radii) :ul
+
+:line
+
+[Restrictions:]
+
+This style is part of the USER-MISC package. It is only enabled if
+LAMMPS is built with that package. See the "Making of
+LAMMPS"_Section_start.html#start_3 section for more info.
+
+[Related commands:]
+
+"pair_coeff"_pair_coeff.html, "pair_style morse"_pair_morse.html
+
+[Default:] none
+
+:line
+
+:link(Grimme)
+[(Grimme)] Grimme, J Comput Chem, 27(15), 1787-1799 (2006).
+
+:link(Fichthorn)
+[(Fichthorn)] Fichthorn, Balankura, Qi, CrystEngComm, 18(29), 5410-5417 (2016).
+
+:link(Zhou4)
+[(Zhou)] Zhou, Saidi, Fichthorn, J Phys Chem C, 118(6), 3366-3374 (2014).

doc/src/pairs.txt

@@ -60,6 +60,7 @@ Pair Styles :h1
    pair_meam_sw_spline
    pair_mgpt
    pair_mie
+   pair_momb
    pair_morse
    pair_multi_lucy
    pair_multi_lucy_rx