This commit is contained in:
Axel Kohlmeyer
2021-07-29 14:44:15 -04:00
parent 5b6b6b8767
commit ebe5e6c024

View File

@ -1,4 +1,3 @@
// clang-format off
/* ---------------------------------------------------------------------- /* ----------------------------------------------------------------------
LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
https://www.lammps.org/, Sandia National Laboratories https://www.lammps.org/, Sandia National Laboratories
@ -20,22 +19,24 @@
------------------------------------------------------------------------- */ ------------------------------------------------------------------------- */
#include "pair_coul_shield.h" #include "pair_coul_shield.h"
#include <cmath>
#include "atom.h" #include "atom.h"
#include "comm.h" #include "comm.h"
#include "force.h"
#include "neighbor.h"
#include "neigh_list.h"
#include "memory.h"
#include "math_special.h"
#include "error.h" #include "error.h"
#include "force.h"
#include "math_special.h"
#include "memory.h"
#include "neigh_list.h"
#include "neighbor.h"
#include <cmath>
using namespace LAMMPS_NS; using namespace LAMMPS_NS;
/* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */
PairCoulShield::PairCoulShield(LAMMPS *lmp) : Pair(lmp) { PairCoulShield::PairCoulShield(LAMMPS *lmp) : Pair(lmp)
{
tap_flag = 1; tap_flag = 1;
} }
@ -109,7 +110,7 @@ void PairCoulShield::compute(int eflag, int vflag)
r3 = rsq * r; r3 = rsq * r;
rarg = 1.0 / sigmae[itype][jtype]; rarg = 1.0 / sigmae[itype][jtype];
th = r3 + MathSpecial::cube(rarg); th = r3 + MathSpecial::cube(rarg);
epsr = 1.0/pow(th,0.333333333333333333333333); epsr = 1.0 / pow(th, 1.0 / 3.0);
depsdr = MathSpecial::square(epsr); depsdr = MathSpecial::square(epsr);
depsdr *= depsdr; depsdr *= depsdr;
Vc = qqrd2e * qtmp * q[j] * epsr; Vc = qqrd2e * qtmp * q[j] * epsr;
@ -118,7 +119,10 @@ void PairCoulShield::compute(int eflag, int vflag)
if (tap_flag) { if (tap_flag) {
Tap = calc_Tap(r, cut[itype][jtype]); Tap = calc_Tap(r, cut[itype][jtype]);
dTap = calc_dTap(r, cut[itype][jtype]); dTap = calc_dTap(r, cut[itype][jtype]);
} else {Tap = 1.0; dTap = 0.0;} } else {
Tap = 1.0;
dTap = 0.0;
}
forcecoul = qqrd2e * qtmp * q[j] * r * depsdr; forcecoul = qqrd2e * qtmp * q[j] * r * depsdr;
fvc = forcecoul * Tap - Vc * dTap / r; fvc = forcecoul * Tap - Vc * dTap / r;
@ -134,13 +138,14 @@ void PairCoulShield::compute(int eflag, int vflag)
} }
if (eflag) { if (eflag) {
if (tap_flag) ecoul = Vc*Tap; if (tap_flag)
else ecoul = Vc - offset[itype][jtype]; ecoul = Vc * Tap;
else
ecoul = Vc - offset[itype][jtype];
ecoul *= factor_coul; ecoul *= factor_coul;
} }
if (evflag) ev_tally(i,j,nlocal,newton_pair,0.0, if (evflag) ev_tally(i, j, nlocal, newton_pair, 0.0, ecoul, fpair, delx, dely, delz);
ecoul,fpair,delx,dely,delz);
} }
} }
} }
@ -159,8 +164,7 @@ void PairCoulShield::allocate()
memory->create(setflag, n + 1, n + 1, "pair:setflag"); memory->create(setflag, n + 1, n + 1, "pair:setflag");
for (int i = 1; i <= n; i++) for (int i = 1; i <= n; i++)
for (int j = i; j <= n; j++) for (int j = i; j <= n; j++) setflag[i][j] = 0;
setflag[i][j] = 0;
memory->create(cutsq, n + 1, n + 1, "pair:cutsq"); memory->create(cutsq, n + 1, n + 1, "pair:cutsq");
memory->create(cut, n + 1, n + 1, "pair:cut"); memory->create(cut, n + 1, n + 1, "pair:cut");
@ -220,15 +224,13 @@ void PairCoulShield::coeff(int narg, char **arg)
if (count == 0) error->all(FLERR, "Incorrect args for pair coefficients"); if (count == 0) error->all(FLERR, "Incorrect args for pair coefficients");
} }
/* ---------------------------------------------------------------------- /* ----------------------------------------------------------------------
init specific to this pair style init specific to this pair style
------------------------------------------------------------------------- */ ------------------------------------------------------------------------- */
void PairCoulShield::init_style() void PairCoulShield::init_style()
{ {
if (!atom->q_flag) if (!atom->q_flag) error->all(FLERR, "Pair style coul/shield requires atom attribute q");
error->all(FLERR,"Pair style coul/shield requires atom attribute q");
if (!atom->molecule_flag) if (!atom->molecule_flag)
error->all(FLERR, "Pair style coul/shield requires atom attribute molecule"); error->all(FLERR, "Pair style coul/shield requires atom attribute molecule");
@ -242,7 +244,8 @@ void PairCoulShield::init_style()
double PairCoulShield::init_one(int i, int j) double PairCoulShield::init_one(int i, int j)
{ {
if (setflag[i][j] == 0) { if (setflag[i][j] == 0) {
error->all(FLERR,"for pair style coul/shield, parameters need to be set explicitly for all pairs."); error->all(FLERR,
"for pair style coul/shield, parameters need to be set explicitly for all pairs.");
} }
double *q = atom->q; double *q = atom->q;
@ -254,10 +257,10 @@ double PairCoulShield::init_one(int i, int j)
r3 = r * r * r; r3 = r * r * r;
rarg = 1.0 / sigmae[i][j]; rarg = 1.0 / sigmae[i][j];
th = r3 + MathSpecial::cube(rarg); th = r3 + MathSpecial::cube(rarg);
epsr = 1.0/pow(th,0.333333333333333333); epsr = 1.0 / pow(th, 1.0/3.0);
offset[i][j] = qqrd2e * q[i] * q[j] * epsr; offset[i][j] = qqrd2e * q[i] * q[j] * epsr;
} else offset[i][j] = 0.0; } else
offset[i][j] = 0.0;
sigmae[j][i] = sigmae[i][j]; sigmae[j][i] = sigmae[i][j];
offset[j][i] = offset[i][j]; offset[j][i] = offset[i][j];
@ -340,9 +343,8 @@ void PairCoulShield::read_restart_settings(FILE *fp)
/* ---------------------------------------------------------------------- */ /* ---------------------------------------------------------------------- */
double PairCoulShield::single(int i, int j, int itype, int jtype, double PairCoulShield::single(int i, int j, int itype, int jtype, double rsq, double factor_coul,
double rsq, double factor_coul, double /*factor_lj*/, double /*factor_lj*/, double &fforce)
double &fforce)
{ {
double r, rarg, Vc, fvc, forcecoul, phishieldec; double r, rarg, Vc, fvc, forcecoul, phishieldec;
double r3, th, epsr, depsdr, Tap, dTap; double r3, th, epsr, depsdr, Tap, dTap;
@ -360,7 +362,7 @@ double PairCoulShield::single(int i, int j, int itype, int jtype,
r3 = rsq * r; r3 = rsq * r;
rarg = 1.0 / sigmae[itype][jtype]; rarg = 1.0 / sigmae[itype][jtype];
th = r3 + MathSpecial::cube(rarg); th = r3 + MathSpecial::cube(rarg);
epsr = 1.0/pow(th,0.333333333333333333); epsr = 1.0 / pow(th, 1.0/3.0);
depsdr = epsr * epsr; depsdr = epsr * epsr;
depsdr *= depsdr; depsdr *= depsdr;
Vc = qqrd2e * q[i] * q[j] * epsr; Vc = qqrd2e * q[i] * q[j] * epsr;
@ -369,13 +371,18 @@ double PairCoulShield::single(int i, int j, int itype, int jtype,
if (tap_flag) { if (tap_flag) {
Tap = calc_Tap(r, cut[itype][jtype]); Tap = calc_Tap(r, cut[itype][jtype]);
dTap = calc_dTap(r, cut[itype][jtype]); dTap = calc_dTap(r, cut[itype][jtype]);
} else {Tap = 1.0; dTap = 0.0;} } else {
Tap = 1.0;
dTap = 0.0;
}
forcecoul = qqrd2e * q[i] * q[j] * r * depsdr; forcecoul = qqrd2e * q[i] * q[j] * r * depsdr;
fvc = forcecoul * Tap - Vc * dTap / r; fvc = forcecoul * Tap - Vc * dTap / r;
fforce = factor_coul * fvc; fforce = factor_coul * fvc;
if (tap_flag) phishieldec = Vc*Tap; if (tap_flag)
else phishieldec = Vc - offset[itype][jtype]; phishieldec = Vc * Tap;
else
phishieldec = Vc - offset[itype][jtype];
return factor_coul * phishieldec; return factor_coul * phishieldec;
} }