diff --git a/doc/src/Eqs/pair_kolmogorov_crespi_z.jpg b/doc/src/Eqs/pair_kolmogorov_crespi_z.jpg
index 0037f3bd54f51f48cc00016ea33ad06219e751ce..3d37ff25be9752bf72a84ce9001d9cacd09a4f51 100644
Binary files a/doc/src/Eqs/pair_kolmogorov_crespi_z.jpg and b/doc/src/Eqs/pair_kolmogorov_crespi_z.jpg differ
diff --git a/doc/src/Eqs/pair_kolmogorov_crespi_z.tex b/doc/src/Eqs/pair_kolmogorov_crespi_z.tex
index 994e8cc33c3412c7c9e27c414dbe96db31f9f524..fb7ebf8dc4c3d38ab23ad25017983e6bdbb71687 100644
--- a/doc/src/Eqs/pair_kolmogorov_crespi_z.tex
+++ b/doc/src/Eqs/pair_kolmogorov_crespi_z.tex
@@ -5,9 +5,9 @@
\begin{eqnarray*}
E & = & \frac{1}{2} \sum_i \sum_{j \neq i} V_{ij} \\
- V_{ij} & = & e^{-\lambda(r_{ij} -z_0}) \left[ C + f(\rho_{ij}) + f(\rho_{ji}) - A \left( \frac{r_{ij}}{z_0}\right)^{-6}\right] \\
- \rho_{ij}^2 & = & x_{ij}^2 + y_{ij}^2 \\
- f(\rho) & = & e^{-(\rho/\delta)^2} \sum_{n=0}^2 C_{2n} { \rho/\delta }^{2n}
+ V_{ij} & = & e^{-\lambda(r_{ij} -z_0}) \left[ C + f(\rho_{ij}) + f(\rho_{ji}) \right] - A \left( \frac{r_{ij}}{z_0}\right)^{-6} + A \left( \frac{\textrm{cutoff}}{z_0}\right)^{-6} \\
+ \rho_{ij}^2 = \rho_{ji}^2 & = & x_{ij}^2 + y_{ij}^2 ~\hspace{2cm} (\mathbf{n_i}\equiv\hat \mathbf{z})\\
+ f(\rho) & = & e^{-(\rho/\delta)^2} \sum_{n=0}^2 C_{2n} \left( \rho/\delta \right) ^{2n}
\end{eqnarray*}
\end{document}
diff --git a/doc/src/pair_kolmogorov_crespi_z.txt b/doc/src/pair_kolmogorov_crespi_z.txt
index 4b0a1fa0e5a5080fed6ff87e8231b64775ab2037..a7bd917caaa5935bb602cbebaf7115d5f03d9137 100644
--- a/doc/src/pair_kolmogorov_crespi_z.txt
+++ b/doc/src/pair_kolmogorov_crespi_z.txt
@@ -10,7 +10,7 @@ pair_style kolmogorov/crespi/z command :h3
[Syntax:]
-pair_style kolmogorov/crespi/z cutoff :pre
+pair_style hybrid/overlay kolmogorov/crespi/z cutoff :pre
[Examples:]
@@ -24,14 +24,26 @@ pair_coeff 1 2 kolmogorov/crespi/z CC.KC C C :pre
[Description:]
-The {kolmogorov/crespi/z} style computes the Kolmogorov-Crespi interaction potential as
-described in "(KC)"_#KC. An important simplification is made, which is to
-take all normals along the z-axis.
+The {kolmogorov/crespi/z} style computes the Kolmogorov-Crespi interaction
+potential as described in "(KC05)"_#KC05. An important simplification is made,
+which is to take all normals along the z-axis.
:c,image(Eqs/pair_kolmogorov_crespi_z.jpg)
+It is important to have a suffiently large cutoff to ensure smooth forces.
+Energies are shifted so that they go continously to zero at the cutoff assuming
+that the exponential part of {Vij} (first term) decays sufficiently fast.
+This shift is achieved by the last term in the equation for {Vij} above.
+
+This potential is intended for interactions between two layers of graphene.
+Therefore, to avoid interaction between layers in multi-layered materials,
+each layer should have a separate atom type and interactions should only
+be computed between atom types of neighbouring layers.
+
The parameter file (e.g. CC.KC), is intended for use with metal
-"units"_units.html, with energies in meV.
+"units"_units.html, with energies in meV. An additional parameter, {S},
+is available to facilitate scaling of energies in accordance with
+"(vanWijk)"_#vanWijk.
This potential must be used in combination with hybrid/overlay.
Other interactions can be set to zero using pair_style {none}.
@@ -46,10 +58,15 @@ LAMMPS"_Section_start.html#start_3 section for more info.
"pair_coeff"_pair_coeff.html
"pair_none"_pair_none.html
+"pair_style hybrid/overlay"_pair_hybrid.html
[Default:] none
:line
-:link(KC)
-[(KC)] Kolmogorov, Crespi, Phys. Rev. B 71, 235415 (2005)
+:link(KC05)
+[(KC05)] A. N. Kolmogorov, V. H. Crespi, Phys. Rev. B 71, 235415 (2005)
+
+:link(vanWijk)
+[(vanWijk)] M. M. van Wijk, A. Schuring, M. I. Katsnelson, and A. Fasolino,
+Physical Review Letters, 113, 135504 (2014)
diff --git a/potentials/CC.KC b/potentials/CC.KC
index f77010cbf1fc3c409e91436a6df3ca0be4766781..6559eb41209f1d9299ecd2aa920049d019d37fd3 100644
--- a/potentials/CC.KC
+++ b/potentials/CC.KC
@@ -2,7 +2,7 @@
#
# Cite as A.N. Kolmogorov & V. H. Crespi,
# Registry-dependent interlayer potential for graphitic systems
-# Physical Review B 71, 2354150 (2005)
+# Physical Review B 71, 235415 (2005)
#
# z0 C0 C2 C4 C delta lambda A S
C C 3.34 15.71 12.29 4.933 3.030 0.578 3.629 10.238 1.0
diff --git a/src/USER-MISC/pair_kolmogorov_crespi_z.cpp b/src/USER-MISC/pair_kolmogorov_crespi_z.cpp
index c4378ef5ea69aee96e41971aca458d54b267f18a..ddb39f6870ad0a9968d739e32bf137207640150b 100644
--- a/src/USER-MISC/pair_kolmogorov_crespi_z.cpp
+++ b/src/USER-MISC/pair_kolmogorov_crespi_z.cpp
@@ -158,11 +158,12 @@ void PairKolmogorovCrespiZ::compute(int eflag, int vflag)
}
if (eflag) {
- evdwl = -p.A*p.z06/r6+ exp1*sumCff+offset[itype][jtype];
+ evdwl = -p.A*p.z06/r6+ exp1*sumCff - offset[itype][jtype];
}
if (evflag){
- ev_tally(i,j,nlocal,newton_pair,evdwl,0.0,fpair,delx,dely,delz);
+ ev_tally_xyz(i,j,nlocal,newton_pair,evdwl,0,
+ fsum,fsum,fpair,delx,dely,delz);
}
}
}
@@ -286,7 +287,8 @@ double PairKolmogorovCrespiZ::init_one(int i, int j)
if (offset_flag) {
int iparam_ij = elem2param[map[i]][map[j]];
- offset[i][j] = params[iparam_ij].A*pow(params[iparam_ij].z0/cut[i][j],6);
+ Param& p = params[iparam_ij];
+ offset[i][j] = -p.A*pow(p.z0/cut[i][j],6);
} else offset[i][j] = 0.0;
offset[j][i] = offset[i][j];