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git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@8825 f3b2605a-c512-4ea7-a41b-209d697bcdaa

This commit is contained in:
sjplimp 2012-10-01 17:19:18 +00:00
parent ad11090106
commit ddd79fe599
3 changed files with 103 additions and 18 deletions
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109
src/fix_efield.cpp
View File

@ -5,7 +5,7 @@
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
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.
@ -41,6 +41,13 @@ FixEfield::FixEfield(LAMMPS *lmp, int narg, char **arg) :
{
if (narg != 6) error->all(FLERR,"Illegal fix efield command");
vector_flag = 1;
scalar_flag = 1;
size_vector = 3;
global_freq = 1;
extvector = 1;
extscalar = 1;
qe2f = force->qe2f;
xstr = ystr = zstr = NULL;
@ -71,6 +78,9 @@ FixEfield::FixEfield(LAMMPS *lmp, int narg, char **arg) :
zstyle = CONSTANT;
}
force_flag = 0;
fsum[0] = fsum[1] = fsum[2] = fsum[3] = 0.0;
maxatom = 0;
efield = NULL;
}
@ -90,8 +100,10 @@ FixEfield::~FixEfield()
int FixEfield::setmask()
{
int mask = 0;
mask |= THERMO_ENERGY;
mask |= POST_FORCE;
mask |= POST_FORCE_RESPA;
mask |= MIN_POST_FORCE;
return mask;
}
@ -105,24 +117,24 @@ void FixEfield::init()
if (xstr) {
xvar = input->variable->find(xstr);
if (xvar < 0) error->all(FLERR,
"Variable name for fix efield does not exist");
if (xvar < 0)
error->all(FLERR,"Variable name for fix efield does not exist");
if (input->variable->equalstyle(xvar)) xstyle = EQUAL;
else if (input->variable->atomstyle(xvar)) xstyle = ATOM;
else error->all(FLERR,"Variable for fix efield is invalid style");
}
if (ystr) {
yvar = input->variable->find(ystr);
if (yvar < 0) error->all(FLERR,
"Variable name for fix efield does not exist");
if (yvar < 0)
error->all(FLERR,"Variable name for fix efield does not exist");
if (input->variable->equalstyle(yvar)) ystyle = EQUAL;
else if (input->variable->atomstyle(yvar)) ystyle = ATOM;
else error->all(FLERR,"Variable for fix efield is invalid style");
}
if (zstr) {
zvar = input->variable->find(zstr);
if (zvar < 0) error->all(FLERR,
"Variable name for fix efield does not exist");
if (zvar < 0)
error->all(FLERR,"Variable name for fix efield does not exist");
if (input->variable->equalstyle(zvar)) zstyle = EQUAL;
else if (input->variable->atomstyle(zvar)) zstyle = ATOM;
else error->all(FLERR,"Variable for fix efield is invalid style");
@ -151,6 +163,13 @@ void FixEfield::setup(int vflag)
}
}
/* ---------------------------------------------------------------------- */
void FixEfield::min_setup(int vflag)
{
post_force(vflag);
}
/* ----------------------------------------------------------------------
apply F = qE
------------------------------------------------------------------------- */
@ -170,12 +189,29 @@ void FixEfield::post_force(int vflag)
memory->create(efield,maxatom,3,"efield:efield");
}
// fsum[0] = "potential energy" for added force
// fsum[123] = extra force added to atoms
fsum[0] = fsum[1] = fsum[2] = fsum[3] = 0.0;
force_flag = 0;
double **x = atom->x;
double fx,fy,fz;
if (varflag == CONSTANT) {
for (int i = 0; i < nlocal; i++)
if (mask[i] & groupbit) {
f[i][0] += q[i]*ex;
f[i][1] += q[i]*ey;
f[i][2] += q[i]*ez;
fx = q[i]*ex;
fy = q[i]*ey;
fz = q[i]*ez;
f[i][0] += fx;
f[i][1] += fy;
f[i][2] += fz;
fsum[0] -= fx*x[i][0]+fy*x[i][1]+fz*x[i][2];
fsum[1] += fx;
fsum[2] += fy;
fsum[3] += fz;
}
// variable efield, wrap with clear/add
@ -198,12 +234,19 @@ void FixEfield::post_force(int vflag)
for (int i = 0; i < nlocal; i++)
if (mask[i] & groupbit) {
if (xstyle == ATOM) f[i][0] += qe2f * q[i]*efield[i][0];
else f[i][0] += q[i]*ex;
if (ystyle == ATOM) f[i][1] += qe2f * q[i]*efield[i][1];
else f[i][1] += q[i]*ey;
if (zstyle == ATOM) f[i][2] += qe2f * q[i]*efield[i][2];
else f[i][2] += q[i]*ez;
if (xstyle == ATOM) fx = qe2f * q[i]*efield[i][0];
else fx = q[i]*ex;
f[i][0] += fx;
fsum[1] += fx;
if (ystyle == ATOM) fy = qe2f * q[i]*efield[i][1];
else fy = q[i]*ey;
f[i][1] += fy;
fsum[2] += fy;
if (zstyle == ATOM) fz = qe2f * q[i]*efield[i][2];
else fz = q[i]*ez;
f[i][2] += fz;
fsum[3] += fz;
fsum[0] -= fx*x[i][0]+fy*x[i][1]+fz*x[i][2];
}
}
}
@ -215,6 +258,13 @@ void FixEfield::post_force_respa(int vflag, int ilevel, int iloop)
if (ilevel == nlevels_respa-1) post_force(vflag);
}
/* ---------------------------------------------------------------------- */
void FixEfield::min_post_force(int vflag)
{
post_force(vflag);
}
/* ----------------------------------------------------------------------
memory usage of local atom-based array
------------------------------------------------------------------------- */
@ -224,4 +274,31 @@ double FixEfield::memory_usage()
double bytes = 0.0;
if (varflag == ATOM) bytes = atom->nmax*3 * sizeof(double);
return bytes;
}
/* ----------------------------------------------------------------------
return energy added by fix
------------------------------------------------------------------------- */
double FixEfield::compute_scalar(void)
{
if (force_flag == 0) {
MPI_Allreduce(fsum,fsum_all,4,MPI_DOUBLE,MPI_SUM,world);
force_flag = 1;
}
return fsum_all[0];
}
/* ----------------------------------------------------------------------
return total extra force due to fix
------------------------------------------------------------------------- */
double FixEfield::compute_vector(int n)
{
if (force_flag == 0) {
MPI_Allreduce(fsum,fsum_all,4,MPI_DOUBLE,MPI_SUM,world);
force_flag = 1;
}
return fsum_all[n+1];
}

10
src/fix_efield.h
View File

@ -5,7 +5,7 @@
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
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.
@ -31,9 +31,13 @@ class FixEfield : public Fix {
int setmask();
void init();
void setup(int);
void min_setup(int);
void post_force(int);
void post_force_respa(int, int, int);
void min_post_force(int);
double memory_usage();
double compute_scalar();
double compute_vector(int);
private:
double ex,ey,ez;
@ -42,9 +46,13 @@ class FixEfield : public Fix {
int xvar,yvar,zvar,xstyle,ystyle,zstyle;
int nlevels_respa;
double qe2f;
double fdotx;
int maxatom;
double **efield;
int force_flag;
double fsum[4],fsum_all[4];
};
}

2
src/pair_gauss.cpp
View File

@ -109,7 +109,7 @@ void PairGauss::compute(int eflag, int vflag)
if (eflag_global && rsq < 0.5/b[itype][jtype]) occ++;
if (rsq < cutsq[itype][jtype]) {
fpair = - 2.0*a[itype][jtype]*b[itype][jtype] *
fpair = -2.0*a[itype][jtype]*b[itype][jtype] *
exp(-b[itype][jtype]*rsq);
f[i][0] += delx*fpair;