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git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@9531 f3b2605a-c512-4ea7-a41b-209d697bcdaa

This commit is contained in:
sjplimp 2013-02-19 15:05:44 +00:00
parent 6ce35d3003
commit 77f659a359
1 changed files with 29 additions and 28 deletions
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57
src/KSPACE/pair_lj_long_coul_long.cpp
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@ -58,13 +58,6 @@ PairLJLongCoulLong::PairLJLongCoulLong(LAMMPS *lmp) : Pair(lmp)
global settings
------------------------------------------------------------------------- */
#define PAIR_ILLEGAL
#define PAIR_CUTOFF
#define PAIR_MISSING
#define PAIR_COUL_CUT
#define PAIR_LARGEST
#define PAIR_MIX
void PairLJLongCoulLong::options(char **arg, int order)
{
const char *option[] = {"long", "cut", "off", NULL};
@ -769,7 +762,7 @@ void PairLJLongCoulLong::compute_middle()
void PairLJLongCoulLong::compute_outer(int eflag, int vflag)
{
double evdwl,ecoul,fpair;
double evdwl,ecoul,fvirial,fpair;
evdwl = ecoul = 0.0;
if (eflag || vflag) ev_setup(eflag,vflag);
else evflag = 0;
@ -825,10 +818,12 @@ void PairLJLongCoulLong::compute_outer(int eflag, int vflag)
r2inv = 1.0/rsq;
frespa = 1.0; // check whether and how to compute respa corrections
respa_coul = 0;
respa_lj = 0;
respa_flag = rsq < cut_in_on_sq ? 1 : 0;
if (respa_flag && (rsq > cut_in_off_sq)) {
register double rsw = (sqrt(rsq)-cut_in_off)/cut_in_diff;
frespa = rsw*rsw*(3.0-2.0*rsw);
frespa = 1-rsw*rsw*(3.0-2.0*rsw);
}
if (order1 && (rsq < cut_coulsq)) { // coulombic
@ -839,19 +834,20 @@ void PairLJLongCoulLong::compute_outer(int eflag, int vflag)
register double x = g_ewald*r, t = 1.0/(1.0+EWALD_P*x);
if (ni == 0) {
s *= g_ewald*exp(-x*x);
force_coul = (t *= ((((t*A5+A4)*t+A3)*t+A2)*t+A1)*s/x)+EWALD_F*s;
force_coul = (t *= ((((t*A5+A4)*t+A3)*t+A2)*t+A1)*s/x)+EWALD_F*s-respa_coul;
if (eflag) ecoul = t;
}
else { // correct for special
r = s*(1.0-special_coul[ni])/r; s *= g_ewald*exp(-x*x);
force_coul = (t *= ((((t*A5+A4)*t+A3)*t+A2)*t+A1)*s/x)+EWALD_F*s-r;
force_coul = (t *= ((((t*A5+A4)*t+A3)*t+A2)*t+A1)*s/x)+EWALD_F*s-r-respa_coul;
if (eflag) ecoul = t-r;
}
} // table real space
else {
if (respa_flag) respa_coul = ni == 0 ? // correct for respa
frespa*qri*q[j]/sqrt(rsq) :
frespa*qri*q[j]/sqrt(rsq)*special_coul[ni];
if (respa_flag) {
register double r = sqrt(rsq), s = qri*q[j];
respa_coul = ni == 0 ? frespa*s/r : frespa*s/r*special_coul[ni];
}
register union_int_float_t t;
t.f = rsq;
register const int k = (t.i & ncoulmask) >> ncoulshiftbits;
@ -863,7 +859,10 @@ void PairLJLongCoulLong::compute_outer(int eflag, int vflag)
else { // correct for special
t.f = (1.0-special_coul[ni])*(ctable[k]+f*dctable[k]);
force_coul = qiqj*(ftable[k]+f*dftable[k]-t.f);
if (eflag) ecoul = qiqj*(etable[k]+f*detable[k]-t.f);
if (eflag) {
t.f = (1.0-special_coul[ni])*(ptable[k]+f*dptable[k]);
ecoul = qiqj*(etable[k]+f*detable[k]-t.f);
}
}
}
}
@ -879,25 +878,25 @@ void PairLJLongCoulLong::compute_outer(int eflag, int vflag)
x2 = a2*exp(-x2)*lj4i[typej];
if (ni == 0) {
force_lj =
(rn*=rn)*lj1i[typej]-g8*(((6.0*a2+6.0)*a2+3.0)*a2+1.0)*x2*rsq;
(rn*=rn)*lj1i[typej]-g8*(((6.0*a2+6.0)*a2+3.0)*a2+1.0)*x2*rsq-respa_lj;
if (eflag) evdwl = rn*lj3i[typej]-g6*((a2+1.0)*a2+0.5)*x2;
}
else { // correct for special
register double f = special_lj[ni], t = rn*(1.0-f);
force_lj = f*(rn *= rn)*lj1i[typej]-
g8*(((6.0*a2+6.0)*a2+3.0)*a2+1.0)*x2*rsq+t*lj2i[typej];
g8*(((6.0*a2+6.0)*a2+3.0)*a2+1.0)*x2*rsq+t*lj2i[typej]-respa_lj;
if (eflag)
evdwl = f*rn*lj3i[typej]-g6*((a2+1.0)*a2+0.5)*x2+t*lj4i[typej];
}
}
else { // cut form
if (ni == 0) {
force_lj = rn*(rn*lj1i[typej]-lj2i[typej]);
force_lj = rn*(rn*lj1i[typej]-lj2i[typej])-respa_lj;
if (eflag) evdwl = rn*(rn*lj3i[typej]-lj4i[typej])-offseti[typej];
}
else { // correct for special
register double f = special_lj[ni];
force_lj = f*rn*(rn*lj1i[typej]-lj2i[typej]);
force_lj = f*rn*(rn*lj1i[typej]-lj2i[typej])-respa_lj;
if (eflag)
evdwl = f*(rn*(rn*lj3i[typej]-lj4i[typej])-offseti[typej]);
}
@ -906,22 +905,24 @@ void PairLJLongCoulLong::compute_outer(int eflag, int vflag)
else force_lj = respa_lj = evdwl = 0.0;
fpair = (force_coul+force_lj)*r2inv;
frespa = respa_flag == 0 ? fpair : fpair-(respa_coul+respa_lj)*r2inv;
if (newton_pair || j < nlocal) {
register double *fj = f0+(j+(j<<1)), f;
fi[0] += f = d[0]*frespa; fj[0] -= f;
fi[1] += f = d[1]*frespa; fj[1] -= f;
fi[2] += f = d[2]*frespa; fj[2] -= f;
fi[0] += f = d[0]*fpair; fj[0] -= f;
fi[1] += f = d[1]*fpair; fj[1] -= f;
fi[2] += f = d[2]*fpair; fj[2] -= f;
}
else {
fi[0] += d[0]*frespa;
fi[1] += d[1]*frespa;
fi[2] += d[2]*frespa;
fi[0] += d[0]*fpair;
fi[1] += d[1]*fpair;
fi[2] += d[2]*fpair;
}
if (evflag) ev_tally(i,j,nlocal,newton_pair,
evdwl,ecoul,fpair,d[0],d[1],d[2]);
if (evflag) {
fvirial = (force_coul + force_lj + respa_coul + respa_lj)*r2inv;
ev_tally(i,j,nlocal,newton_pair,
evdwl,ecoul,fvirial,d[0],d[1],d[2]);
}
}
}
}