Page Menu
Home
c4science
Search
Configure Global Search
Log In
Files
F78390017
pair_nm_cut_coul_cut.cpp
No One
Temporary
Actions
Download File
Edit File
Delete File
View Transforms
Subscribe
Mute Notifications
Award Token
Subscribers
None
File Metadata
Details
File Info
Storage
Attached
Created
Tue, Aug 20, 13:31
Size
15 KB
Mime Type
text/x-c
Expires
Thu, Aug 22, 13:31 (1 d, 22 h)
Engine
blob
Format
Raw Data
Handle
18779426
Attached To
rLAMMPS lammps
pair_nm_cut_coul_cut.cpp
View Options
/* ----------------------------------------------------------------------
LAMMPS - Large-scale Atomic/Molecular Massively Parallel Simulator
http://lammps.sandia.gov, Sandia National Laboratories
Steve Plimpton, sjplimp@sandia.gov
Copyright (2003) Sandia Corporation. Under the terms of Contract
DE-AC04-94AL85000 with Sandia Corporation, the U.S. Government retains
certain rights in this software. This software is distributed under
the GNU General Public License.
See the README file in the top-level LAMMPS directory.
------------------------------------------------------------------------- */
/* ----------------------------------------------------------------------
Contributing Author: Julien Devemy (ICCF)
------------------------------------------------------------------------- */
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "pair_nm_cut_coul_cut.h"
#include "atom.h"
#include "comm.h"
#include "force.h"
#include "neighbor.h"
#include "neigh_list.h"
#include "math_const.h"
#include "memory.h"
#include "error.h"
using namespace LAMMPS_NS;
using namespace MathConst;
/* ---------------------------------------------------------------------- */
PairNMCutCoulCut::PairNMCutCoulCut(LAMMPS *lmp) : Pair(lmp)
{
writedata = 1;
}
/* ---------------------------------------------------------------------- */
PairNMCutCoulCut::~PairNMCutCoulCut()
{
if (allocated) {
memory->destroy(setflag);
memory->destroy(cutsq);
memory->destroy(cut_lj);
memory->destroy(cut_ljsq);
memory->destroy(cut_coul);
memory->destroy(cut_coulsq);
memory->destroy(e0);
memory->destroy(r0);
memory->destroy(nn);
memory->destroy(mm);
memory->destroy(nm);
memory->destroy(e0nm);
memory->destroy(r0n);
memory->destroy(r0m);
memory->destroy(offset);
}
}
/* ---------------------------------------------------------------------- */
void PairNMCutCoulCut::compute(int eflag, int vflag)
{
int i,j,ii,jj,inum,jnum,itype,jtype;
double qtmp,xtmp,ytmp,ztmp,delx,dely,delz,evdwl,ecoul,fpair;
double rsq,r2inv,factor_coul,factor_lj;
double r,forcecoul,forcenm,rminv,rninv;
int *ilist,*jlist,*numneigh,**firstneigh;
evdwl = ecoul = 0.0;
if (eflag || vflag) ev_setup(eflag,vflag);
else evflag = vflag_fdotr = 0;
double **x = atom->x;
double **f = atom->f;
double *q = atom->q;
int *type = atom->type;
int nlocal = atom->nlocal;
double *special_coul = force->special_coul;
double *special_lj = force->special_lj;
int newton_pair = force->newton_pair;
double qqrd2e = force->qqrd2e;
inum = list->inum;
ilist = list->ilist;
numneigh = list->numneigh;
firstneigh = list->firstneigh;
// loop over neighbors of my atoms
for (ii = 0; ii < inum; ii++) {
i = ilist[ii];
qtmp = q[i];
xtmp = x[i][0];
ytmp = x[i][1];
ztmp = x[i][2];
itype = type[i];
jlist = firstneigh[i];
jnum = numneigh[i];
for (jj = 0; jj < jnum; jj++) {
j = jlist[jj];
factor_lj = special_lj[sbmask(j)];
factor_coul = special_coul[sbmask(j)];
j &= NEIGHMASK;
delx = xtmp - x[j][0];
dely = ytmp - x[j][1];
delz = ztmp - x[j][2];
rsq = delx*delx + dely*dely + delz*delz;
jtype = type[j];
if (rsq < cutsq[itype][jtype]) {
r2inv = 1.0/rsq;
if (rsq < cut_coulsq[itype][jtype])
forcecoul = qqrd2e * qtmp*q[j]*sqrt(r2inv);
else forcecoul = 0.0;
if (rsq < cut_ljsq[itype][jtype]) {
r = sqrt(rsq);
rminv = pow(r2inv,mm[itype][jtype]/2.0);
rninv = pow(r2inv,nn[itype][jtype]/2.0);
forcenm = e0nm[itype][jtype]*nm[itype][jtype] *
(r0n[itype][jtype]/pow(r,nn[itype][jtype]) -
r0m[itype][jtype]/pow(r,mm[itype][jtype]));
} else forcenm = 0.0;
fpair = (factor_coul*forcecoul + factor_lj*forcenm) * r2inv;
f[i][0] += delx*fpair;
f[i][1] += dely*fpair;
f[i][2] += delz*fpair;
if (newton_pair || j < nlocal) {
f[j][0] -= delx*fpair;
f[j][1] -= dely*fpair;
f[j][2] -= delz*fpair;
}
if (eflag) {
if (rsq < cut_coulsq[itype][jtype])
ecoul = factor_coul * qqrd2e * qtmp*q[j]*sqrt(r2inv);
else ecoul = 0.0;
if (rsq < cut_ljsq[itype][jtype]) {
evdwl = e0nm[itype][jtype]*(mm[itype][jtype] *
r0n[itype][jtype]*rninv -
nn[itype][jtype] *
r0m[itype][jtype]*rminv) -
offset[itype][jtype];
evdwl *= factor_lj;
} else evdwl = 0.0;
}
if (evflag) ev_tally(i,j,nlocal,newton_pair,
evdwl,ecoul,fpair,delx,dely,delz);
}
}
}
if (vflag_fdotr) virial_fdotr_compute();
}
/* ----------------------------------------------------------------------
allocate all arrays
------------------------------------------------------------------------- */
void PairNMCutCoulCut::allocate()
{
allocated = 1;
int n = atom->ntypes;
memory->create(setflag,n+1,n+1,"pair:setflag");
for (int i = 1; i <= n; i++)
for (int j = i; j <= n; j++)
setflag[i][j] = 0;
memory->create(cutsq,n+1,n+1,"pair:cutsq");
memory->create(cut_lj,n+1,n+1,"pair:cut_lj");
memory->create(cut_ljsq,n+1,n+1,"pair:cut_ljsq");
memory->create(cut_coul,n+1,n+1,"pair:cut_coul");
memory->create(cut_coulsq,n+1,n+1,"pair:cut_coulsq");
memory->create(e0,n+1,n+1,"pair:e0");
memory->create(r0,n+1,n+1,"pair:r0");
memory->create(nn,n+1,n+1,"pair:nn");
memory->create(mm,n+1,n+1,"pair:mm");
memory->create(nm,n+1,n+1,"pair:nm");
memory->create(e0nm,n+1,n+1,"pair:e0nm");
memory->create(r0n,n+1,n+1,"pair:r0n");
memory->create(r0m,n+1,n+1,"pair:r0m");
memory->create(offset,n+1,n+1,"pair:offset");
}
/* ----------------------------------------------------------------------
global settings
------------------------------------------------------------------------- */
void PairNMCutCoulCut::settings(int narg, char **arg)
{
if (narg < 1 || narg > 2) error->all(FLERR,"Illegal pair_style command");
cut_lj_global = force->numeric(FLERR,arg[0]);
if (narg == 1) cut_coul_global = cut_lj_global;
else cut_coul_global = force->numeric(FLERR,arg[1]);
// reset cutoffs that have been explicitly set
if (allocated) {
int i,j;
for (i = 1; i <= atom->ntypes; i++)
for (j = i+1; j <= atom->ntypes; j++)
if (setflag[i][j]) {
cut_lj[i][j] = cut_lj_global;
cut_coul[i][j] = cut_coul_global;
}
}
}
/* ----------------------------------------------------------------------
set coeffs for one or more type pairs
------------------------------------------------------------------------- */
void PairNMCutCoulCut::coeff(int narg, char **arg)
{
if (narg < 6 || narg > 8)
error->all(FLERR,"Incorrect args for pair coefficients");
if (!allocated) allocate();
int ilo,ihi,jlo,jhi;
force->bounds(arg[0],atom->ntypes,ilo,ihi);
force->bounds(arg[1],atom->ntypes,jlo,jhi);
double e0_one = force->numeric(FLERR,arg[2]);
double r0_one = force->numeric(FLERR,arg[3]);
double nn_one = force->numeric(FLERR,arg[4]);
double mm_one = force->numeric(FLERR,arg[5]);
double cut_lj_one = cut_lj_global;
double cut_coul_one = cut_coul_global;
if (narg >= 7) cut_coul_one = cut_lj_one = force->numeric(FLERR,arg[4]);
if (narg == 8) cut_coul_one = force->numeric(FLERR,arg[5]);
int count = 0;
for (int i = ilo; i <= ihi; i++) {
for (int j = MAX(jlo,i); j <= jhi; j++) {
e0[i][j] = e0_one;
r0[i][j] = r0_one;
nn[i][j] = nn_one;
mm[i][j] = mm_one;
cut_lj[i][j] = cut_lj_one;
cut_coul[i][j] = cut_coul_one;
setflag[i][j] = 1;
count++;
}
}
if (count == 0) error->all(FLERR,"Incorrect args for pair coefficients");
}
/* ----------------------------------------------------------------------
init specific to this pair style
------------------------------------------------------------------------- */
void PairNMCutCoulCut::init_style()
{
if (!atom->q_flag)
error->all(FLERR,"Pair style nm/cut/coul/cut requires atom attribute q");
neighbor->request(this,instance_me);
}
/* ----------------------------------------------------------------------
init for one type pair i,j and corresponding j,i
------------------------------------------------------------------------- */
double PairNMCutCoulCut::init_one(int i, int j)
{
if (setflag[i][j] == 0) error->all(FLERR,"All pair coeffs are not set");
double cut = MAX(cut_lj[i][j],cut_coul[i][j]);
cut_ljsq[i][j] = cut_lj[i][j] * cut_lj[i][j];
cut_coulsq[i][j] = cut_coul[i][j] * cut_coul[i][j];
nm[i][j] = nn[i][j]*mm[i][j];
e0nm[i][j] = e0[i][j]/(nn[i][j]-mm[i][j]);
r0n[i][j] = pow(r0[i][j],nn[i][j]);
r0m[i][j] = pow(r0[i][j],mm[i][j]);
if (offset_flag) {
offset[i][j] = e0nm[i][j] *
((mm[i][j]*r0n[i][j] / pow(cut_lj[i][j],nn[i][j])) -
(nn[i][j]*r0m[i][j] / pow(cut_lj[i][j],mm[i][j])));
} else offset[i][j] = 0.0;
cut_ljsq[j][i] = cut_ljsq[i][j];
cut_coulsq[j][i] = cut_coulsq[i][j];
e0[j][i] = e0[i][j];
nn[j][i] = nn[i][j];
mm[j][i] = mm[i][j];
nm[j][i] = nm[i][j];
r0[j][i] = r0[i][j];
e0nm[j][i] = e0nm[i][j];
r0n[j][i] = r0n[i][j];
r0m[j][i] = r0m[i][j];
offset[j][i] = offset[i][j];
// compute I,J contribution to long-range tail correction
// count total # of atoms of type I and J via Allreduce
if (tail_flag) {
int *type = atom->type;
int nlocal = atom->nlocal;
double count[2],all[2];
count[0] = count[1] = 0.0;
for (int k = 0; k < nlocal; k++) {
if (type[k] == i) count[0] += 1.0;
if (type[k] == j) count[1] += 1.0;
}
MPI_Allreduce(count,all,2,MPI_DOUBLE,MPI_SUM,world);
double rr1 = mm[i][j]*(nn[i][j]-1)*pow(r0[i][j],nn[i][j]);
double rr2 = nn[i][j]*(mm[i][j]-1)*pow(r0[i][j],mm[i][j]);
double p1 = 1-nn[i][j];
double p2 = 1-mm[i][j];
double rrr1 = pow(r0[i][j],nn[i][j])*(1-nn[i][j]);
double rrr2 = pow(r0[i][j],mm[i][j])*(1-mm[i][j]);
etail_ij = 2.0*MY_PI*all[0]*all[1]*e0nm[i][j] *
(rr1*pow(cut_lj[i][j],p1)-rr2*pow(cut_lj[i][j],p2));
ptail_ij = 2.0*MY_PI*all[0]*all[1]*e0nm[i][j] *
nn[i][j]*mm[i][j]*(rrr1*pow(cut_lj[i][j],p1)-rrr2*pow(cut_lj[i][j],p2));
}
return cut;
}
/* ----------------------------------------------------------------------
proc 0 writes to restart file
------------------------------------------------------------------------- */
void PairNMCutCoulCut::write_restart(FILE *fp)
{
write_restart_settings(fp);
int i,j;
for (i = 1; i <= atom->ntypes; i++)
for (j = i; j <= atom->ntypes; j++) {
fwrite(&setflag[i][j],sizeof(int),1,fp);
if (setflag[i][j]) {
fwrite(&e0[i][j],sizeof(double),1,fp);
fwrite(&r0[i][j],sizeof(double),1,fp);
fwrite(&nn[i][j],sizeof(double),1,fp);
fwrite(&mm[i][j],sizeof(double),1,fp);
fwrite(&cut_lj[i][j],sizeof(double),1,fp);
fwrite(&cut_coul[i][j],sizeof(double),1,fp);
}
}
}
/* ----------------------------------------------------------------------
proc 0 reads from restart file, bcasts
------------------------------------------------------------------------- */
void PairNMCutCoulCut::read_restart(FILE *fp)
{
read_restart_settings(fp);
allocate();
int i,j;
int me = comm->me;
for (i = 1; i <= atom->ntypes; i++)
for (j = i; j <= atom->ntypes; j++) {
if (me == 0) fread(&setflag[i][j],sizeof(int),1,fp);
MPI_Bcast(&setflag[i][j],1,MPI_INT,0,world);
if (setflag[i][j]) {
if (me == 0) {
fread(&e0[i][j],sizeof(double),1,fp);
fread(&r0[i][j],sizeof(double),1,fp);
fread(&nn[i][j],sizeof(double),1,fp);
fread(&mm[i][j],sizeof(double),1,fp);
fread(&cut_lj[i][j],sizeof(double),1,fp);
fread(&cut_coul[i][j],sizeof(double),1,fp);
}
MPI_Bcast(&e0[i][j],1,MPI_DOUBLE,0,world);
MPI_Bcast(&r0[i][j],1,MPI_DOUBLE,0,world);
MPI_Bcast(&nn[i][j],1,MPI_DOUBLE,0,world);
MPI_Bcast(&mm[i][j],1,MPI_DOUBLE,0,world);
MPI_Bcast(&cut_lj[i][j],1,MPI_DOUBLE,0,world);
MPI_Bcast(&cut_coul[i][j],1,MPI_DOUBLE,0,world);
}
}
}
/* ----------------------------------------------------------------------
proc 0 writes to restart file
------------------------------------------------------------------------- */
void PairNMCutCoulCut::write_restart_settings(FILE *fp)
{
fwrite(&cut_lj_global,sizeof(double),1,fp);
fwrite(&cut_coul_global,sizeof(double),1,fp);
fwrite(&offset_flag,sizeof(int),1,fp);
fwrite(&mix_flag,sizeof(int),1,fp);
fwrite(&tail_flag,sizeof(int),1,fp);
}
/* ----------------------------------------------------------------------
proc 0 reads from restart file, bcasts
------------------------------------------------------------------------- */
void PairNMCutCoulCut::read_restart_settings(FILE *fp)
{
if (comm->me == 0) {
fread(&cut_lj_global,sizeof(double),1,fp);
fread(&cut_coul_global,sizeof(double),1,fp);
fread(&offset_flag,sizeof(int),1,fp);
fread(&mix_flag,sizeof(int),1,fp);
fread(&tail_flag,sizeof(int),1,fp);
}
MPI_Bcast(&cut_lj_global,1,MPI_DOUBLE,0,world);
MPI_Bcast(&cut_coul_global,1,MPI_DOUBLE,0,world);
MPI_Bcast(&offset_flag,1,MPI_INT,0,world);
MPI_Bcast(&mix_flag,1,MPI_INT,0,world);
MPI_Bcast(&tail_flag,1,MPI_INT,0,world);
}
/* ----------------------------------------------------------------------
proc 0 writes to data file
------------------------------------------------------------------------- */
void PairNMCutCoulCut::write_data(FILE *fp)
{
for (int i = 1; i <= atom->ntypes; i++)
fprintf(fp,"%d %g %g %g %g\n",i,e0[i][i],r0[i][i],nn[i][i],mm[i][i]);
}
/* ----------------------------------------------------------------------
proc 0 writes all pairs to data file
------------------------------------------------------------------------- */
void PairNMCutCoulCut::write_data_all(FILE *fp)
{
for (int i = 1; i <= atom->ntypes; i++)
for (int j = i; j <= atom->ntypes; j++)
fprintf(fp,"%d %d %g %g %g %g %g\n",i,j,
e0[i][j],r0[i][j],nn[i][j],mm[i][j],cut_lj[i][j]);
}
/* ---------------------------------------------------------------------- */
double PairNMCutCoulCut::single(int i, int j, int itype, int jtype,
double rsq,
double factor_coul, double factor_lj,
double &fforce)
{
double r2inv,r,forcecoul,forcenm,phicoul,phinm;
r2inv = 1.0/rsq;
if (rsq < cut_coulsq[itype][jtype])
forcecoul = force->qqrd2e * atom->q[i]*atom->q[j]*sqrt(r2inv);
else forcecoul = 0.0;
if (rsq < cut_ljsq[itype][jtype]) {
r = sqrt(rsq);
forcenm = e0nm[itype][jtype]*nm[itype][jtype] *
(r0n[itype][jtype]/pow(r,nn[itype][jtype]) -
r0m[itype][jtype]/pow(r,mm[itype][jtype]));
} else forcenm = 0.0;
fforce = (factor_coul*forcecoul + factor_lj*forcenm) * r2inv;
double eng = 0.0;
if (rsq < cut_coulsq[itype][jtype]) {
phicoul = force->qqrd2e * atom->q[i]*atom->q[j]*sqrt(r2inv);
eng += factor_coul*phicoul;
}
if (rsq < cut_ljsq[itype][jtype]) {
phinm = e0nm[itype][jtype] *
(mm[itype][jtype]*r0n[itype][jtype]/pow(r,nn[itype][jtype]) -
nn[itype][jtype]*r0m[itype][jtype]/pow(r,mm[itype][jtype])) -
offset[itype][jtype];
eng += factor_lj*phinm;
}
return eng;
}
/* ---------------------------------------------------------------------- */
void *PairNMCutCoulCut::extract(const char *str, int &dim)
{
dim = 0;
if (strcmp(str,"cut_coul") == 0) return (void *) &cut_coul;
dim = 2;
if (strcmp(str,"e0") == 0) return (void *) e0;
if (strcmp(str,"r0") == 0) return (void *) r0;
if (strcmp(str,"nn") == 0) return (void *) nn;
if (strcmp(str,"mm") == 0) return (void *) mm;
return NULL;
}
Event Timeline
Log In to Comment