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Commit1 JT 081618

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- converted pppm_spin for long range spin-spin interactions
- modified kspace, pair,and pair_hybrid to add spinflag
This commit is contained in:
julient31
2018-08-16 10:13:18 -06:00
parent e1ab38439b
commit 5e287033f7
8 changed files with 70 additions and 88 deletions
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138
src/KSPACE/pppm_spin.cpp
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@ -115,13 +115,7 @@ void PPPMSpin::init()
// error check
//spinflag = atom->mu?1:0;
spinflag = atom->sp?1:0;
// no charges here, charge neutrality
//qsum_qsq(0);
// maybe change this test
if (spinflag && q2)
error->all(FLERR,"Cannot (yet) uses charges with Kspace style PPPMSpin");
triclinic_check();
@ -175,17 +169,12 @@ void PPPMSpin::init()
if (tip4pflag)
error->all(FLERR,"Cannot yet use TIP4P with PPPMSpin");
// compute qsum & qsqsum and warn if not charge-neutral
scale = 1.0;
//qqrd2e = force->qqrd2e;
// need to define mag constants instead
hbar = force->hplanck/MY_2PI; // eV/(rad.THz)
mub = 5.78901e-5; // in eV/T
mu_0 = 1.2566370614e-6; // in T.m/A
mub2mu0 = mub * mub * mu_0; // in eV
mub2mu0hbinv = mub2mu0 / hbar; // in rad.THz
//musum_musq();
spsum_spsq();
natoms_original = atom->natoms;
@ -458,7 +447,6 @@ void PPPMSpin::compute(int eflag, int vflag)
// if atom count has changed, update qsum and qsqsum
if (atom->natoms != natoms_original) {
//musum_musq();
spsum_spsq();
natoms_original = atom->natoms;
}
@ -520,7 +508,6 @@ void PPPMSpin::compute(int eflag, int vflag)
// sum global energy across procs and add in volume-dependent term
//const double qscale = qqrd2e * scale;
const double spscale = mub2mu0 * scale;
const double g3 = g_ewald*g_ewald*g_ewald;
@ -531,7 +518,7 @@ void PPPMSpin::compute(int eflag, int vflag)
energy *= 0.5*volume;
energy -= spsqsum*2.0*g3/3.0/MY_PIS;
energy *= qscale;
energy *= spscale;
}
// sum global virial across procs
@ -539,32 +526,32 @@ void PPPMSpin::compute(int eflag, int vflag)
if (vflag_global) {
double virial_all[6];
MPI_Allreduce(virial,virial_all,6,MPI_DOUBLE,MPI_SUM,world);
for (i = 0; i < 6; i++) virial[i] = 0.5*qscale*volume*virial_all[i];
for (i = 0; i < 6; i++) virial[i] = 0.5*spscale*volume*virial_all[i];
}
// per-atom energy/virial
// energy includes self-energy correction
if (evflag_atom) {
//double *q = atom->q;
//double **mu = atom->mu;
double **sp = atom->sp;
double spx,spy,spz;
int nlocal = atom->nlocal;
int ntotal = nlocal;
if (eflag_atom) {
for (i = 0; i < nlocal; i++) {
spx = sp[i][0]*sp[i][3];
spy = sp[i][1]*sp[i][3];
spz = sp[i][2]*sp[i][3];
eatom[i] *= 0.5;
//eatom[i] -= (mu[i][0]*mu[i][0] + mu[i][1]*mu[i][1] + mu[i][2]*mu[i][2])*2.0*g3/3.0/MY_PIS;
eatom[i] -= (sp[i][0]*sp[i][0] + sp[i][1]*sp[i][1] + sp[i][2]*sp[i][2])*2.0*g3/3.0/MY_PIS;
//eatom[i] *= qscale;
eatom[i] -= (spx*spx + spy*spy + spz*spz)*2.0*g3/3.0/MY_PIS;
eatom[i] *= spscale;
}
}
if (vflag_atom) {
for (i = 0; i < ntotal; i++)
for (j = 0; j < 6; j++) vatom[i][j] *= 0.5*qscale;
for (j = 0; j < 6; j++) vatom[i][j] *= 0.5*spscale;
}
}
@ -918,7 +905,6 @@ double PPPMSpin::compute_df_kspace_spin()
double zprd_slab = zprd*slab_volfactor;
bigint natoms = atom->natoms;
double qopt = compute_qopt_spin();
//double df_kspace = sqrt(qopt/natoms)*mu2/(3.0*xprd*yprd*zprd_slab);
double df_kspace = sqrt(qopt/natoms)*sp2/(3.0*xprd*yprd*zprd_slab);
return df_kspace;
}
@ -1131,8 +1117,6 @@ double PPPMSpin::newton_raphson_f()
double rg6 = rg4*rg2;
double Cc = 4.0*rg4 + 6.0*rg2 + 3.0;
double Dc = 8.0*rg6 + 20.0*rg4 + 30.0*rg2 + 15.0;
//df_rspace = (mu2/(sqrt(vol*powint(g_ewald,4)*powint(cutoff,9)*natoms)) *
// sqrt(13.0/6.0*Cc*Cc + 2.0/15.0*Dc*Dc - 13.0/15.0*Cc*Dc) * exp(-rg2));
df_rspace = (sp2/(sqrt(vol*powint(g_ewald,4)*powint(cutoff,9)*natoms)) *
sqrt(13.0/6.0*Cc*Cc + 2.0/15.0*Dc*Dc - 13.0/15.0*Cc*Dc) * exp(-rg2));
df_kspace = compute_df_kspace_spin();
@ -1218,9 +1202,6 @@ double PPPMSpin::final_accuracy_spin()
double rg6 = rg4*rg2;
double Cc = 4.0*rg4 + 6.0*rg2 + 3.0;
double Dc = 8.0*rg6 + 20.0*rg4 + 30.0*rg2 + 15.0;
//double df_rspace = (mu2/(sqrt(vol*powint(g_ewald,4)*powint(cutoff,9)*natoms)) *
// sqrt(13.0/6.0*Cc*Cc + 2.0/15.0*Dc*Dc - 13.0/15.0*Cc*Dc) *
// exp(-rg2));
double df_rspace = (sp2/(sqrt(vol*powint(g_ewald,4)*powint(cutoff,9)*natoms)) *
sqrt(13.0/6.0*Cc*Cc + 2.0/15.0*Dc*Dc - 13.0/15.0*Cc*Dc) *
exp(-rg2));
@ -1285,8 +1266,8 @@ void PPPMSpin::make_rho_spin()
// (dx,dy,dz) = distance to "lower left" grid pt
// (mx,my,mz) = global coords of moving stencil pt
//double **mu = atom->mu;
double **sp = atom->sp;
double spx,spy,spz;
double **x = atom->x;
int nlocal = atom->nlocal;
@ -1301,9 +1282,12 @@ void PPPMSpin::make_rho_spin()
compute_rho1d(dx,dy,dz);
z0 = delvolinv * sp[i][0];
z1 = delvolinv * sp[i][1];
z2 = delvolinv * sp[i][2];
spx = sp[i][0]*sp[i][3];
spy = sp[i][1]*sp[i][3];
spz = sp[i][2]*sp[i][3];
z0 = delvolinv * spx;
z1 = delvolinv * spy;
z2 = delvolinv * spz;
for (n = nlower; n <= nupper; n++) {
mz = n+nz;
y0 = z0*rho1d[2][n];
@ -2076,13 +2060,11 @@ void PPPMSpin::fieldforce_ik_spin()
// (dx,dy,dz) = distance to "lower left" grid pt
// (mx,my,mz) = global coords of moving stencil pt
//double **mu = atom->mu;
double **sp = atom->sp;
double spx,spy,spz;
double **x = atom->x;
double **f = atom->f;
double **fm = atom->fm;
double **t = atom->torque;
int nlocal = atom->nlocal;
@ -2120,16 +2102,15 @@ void PPPMSpin::fieldforce_ik_spin()
}
}
// convert E-field to torque
// convert M-field to mech. and mag. forces
//const double mufactor = qqrd2e * scale;
const double spfactor = mub2mu0 * scale;
//f[i][0] += mufactor*(vxx*mu[i][0] + vxy*mu[i][1] + vxz*mu[i][2]);
//f[i][1] += mufactor*(vxy*mu[i][0] + vyy*mu[i][1] + vyz*mu[i][2]);
//f[i][2] += mufactor*(vxz*mu[i][0] + vyz*mu[i][1] + vzz*mu[i][2]);
f[i][0] += spfactor*(vxx*sp[i][0] + vxy*sp[i][1] + vxz*sp[i][2]);
f[i][1] += spfactor*(vxy*sp[i][0] + vyy*sp[i][1] + vyz*sp[i][2]);
f[i][2] += spfactor*(vxz*sp[i][0] + vyz*sp[i][1] + vzz*sp[i][2]);
spx = sp[i][0]*sp[i][3];
spy = sp[i][1]*sp[i][3];
spz = sp[i][2]*sp[i][3];
f[i][0] += spfactor*(vxx*spx + vxy*spy + vxz*spz);
f[i][1] += spfactor*(vxy*spx + vyy*spy + vyz*spz);
f[i][2] += spfactor*(vxz*spx + vyz*spy + vzz*spz);
const double spfactorh = mub2mu0hbinv * scale;
fm[i][0] += spfactorh*ex;
@ -2159,8 +2140,8 @@ void PPPMSpin::fieldforce_peratom_spin()
// (dx,dy,dz) = distance to "lower left" grid pt
// (mx,my,mz) = global coords of moving stencil pt
//double **mu = atom->mu;
double **sp = atom->sp;
double spx,spy,spz;
double **x = atom->x;
int nlocal = atom->nlocal;
@ -2217,14 +2198,17 @@ void PPPMSpin::fieldforce_peratom_spin()
}
}
if (eflag_atom) eatom[i] += sp[i][0]*ux + sp[i][1]*uy + sp[i][2]*uz;
spx = sp[i][0]*sp[i][3];
spy = sp[i][1]*sp[i][3];
spz = sp[i][2]*sp[i][3];
if (eflag_atom) eatom[i] += spx*ux + spy*uy + spz*uz;
if (vflag_atom) {
vatom[i][0] += sp[i][0]*v0x + sp[i][1]*v0y + sp[i][2]*v0z;
vatom[i][1] += sp[i][0]*v1x + sp[i][1]*v1y + sp[i][2]*v1z;
vatom[i][2] += sp[i][0]*v2x + sp[i][1]*v2y + sp[i][2]*v2z;
vatom[i][3] += sp[i][0]*v3x + sp[i][1]*v3y + sp[i][2]*v3z;
vatom[i][4] += sp[i][0]*v4x + sp[i][1]*v4y + sp[i][2]*v4z;
vatom[i][5] += sp[i][0]*v5x + sp[i][1]*v5y + sp[i][2]*v5z;
vatom[i][0] += spx*v0x + spy*v0y + spz*v0z;
vatom[i][1] += spx*v1x + spy*v1y + spz*v1z;
vatom[i][2] += spx*v2x + spy*v2y + spz*v2z;
vatom[i][3] += spx*v3x + spy*v3y + spz*v3z;
vatom[i][4] += spx*v4x + spy*v4y + spz*v4z;
vatom[i][5] += spx*v5x + spy*v5y + spz*v5z;
}
}
}
@ -2426,28 +2410,21 @@ void PPPMSpin::slabcorr()
int nlocal = atom->nlocal;
double spin = 0.0;
//double **mu = atom->mu;
double **sp = atom->sp;
for (int i = 0; i < nlocal; i++) spin += sp[i][2];
double spx,spy,spz;
for (int i = 0; i < nlocal; i++) {
spz = sp[i][2]*sp[i][3];
spin += spz;
}
// sum local contributions to get global spin moment
double spin_all;
MPI_Allreduce(&spin,&spin_all,1,MPI_DOUBLE,MPI_SUM,world);
// need to make non-neutral systems and/or
// per-atom energy translationally invariant
if (eflag_atom || fabs(qsum) > SMALL) {
error->all(FLERR,"Cannot (yet) use kspace slab correction with "
"long-range spins and non-neutral systems or per-atom energy");
}
// compute corrections
const double e_slabcorr = MY_2PI*(spin_all*spin_all/12.0)/volume;
//const double qscale = qqrd2e * scale;
const double spscale = mub2mu0 * scale;
if (eflag_global) energy += spscale * e_slabcorr;
@ -2455,27 +2432,20 @@ void PPPMSpin::slabcorr()
// per-atom energy
if (eflag_atom) {
//double efact = qscale * MY_2PI/volume/12.0;
double efact = spscale * MY_2PI/volume/12.0;
for (int i = 0; i < nlocal; i++)
//eatom[i] += efact * mu[i][2]*spin_all;
eatom[i] += efact * sp[i][2]*spin_all;
for (int i = 0; i < nlocal; i++) {
spz = sp[i][2]*sp[i][3];
eatom[i] += efact * spz * spin_all;
}
}
// add on torque corrections
// add on mag. force corrections
// no torque for the spins
// should it be calculated for the magnetic force fm?
//if (atom->torque) {
// double ffact = qscale * (-4.0*MY_PI/volume);
// double **mu = atom->mu;
// double **torque = atom->torque;
// for (int i = 0; i < nlocal; i++) {
// torque[i][0] += ffact * spin_all * mu[i][1];
// torque[i][1] += -ffact * spin_all * mu[i][0];
// }
//}
double ffact = spscale * (-4.0*MY_PI/volume);
double **fm = atom->fm;
for (int i = 0; i < nlocal; i++) {
fm[i][2] += ffact * spin_all;
}
}
/* ----------------------------------------------------------------------
@ -2584,20 +2554,22 @@ void PPPMSpin::spsum_spsq()
spsum = spsqsum = sp2 = 0.0;
if (atom->sp_flag) {
double **sp = atom->sp;
double spx, spy, spz;
double spsum_local(0.0), spsqsum_local(0.0);
// not exactly the good loop: need to add norm of spins
for (int i = 0; i < nlocal; i++) {
spsum_local += sp[i][0] + sp[i][1] + sp[i][2];
spsqsum_local += sp[i][0]*sp[i][0] + sp[i][1]*sp[i][1] + sp[i][2]*sp[i][2];
spx = sp[i][0]*sp[i][3];
spy = sp[i][1]*sp[i][3];
spz = sp[i][2]*sp[i][3];
spsum_local += spx + spy + spz;
spsqsum_local += spx*spx + spy*spy + spz*spz;
}
MPI_Allreduce(&spsum_local,&spsum,1,MPI_DOUBLE,MPI_SUM,world);
MPI_Allreduce(&spsqsum_local,&spsqsum,1,MPI_DOUBLE,MPI_SUM,world);
//mu2 = musqsum * force->qqrd2e;
// find correct units
sp2 = spsqsum * mub2mu0;
}

9
src/KSPACE/pppm_spin.h
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@ -37,6 +37,11 @@ class PPPMSpin : public PPPM {
double memory_usage();
protected:
double hbar; // reduced Planck's constant
double mub; // Bohr's magneton
double mu_0; // vacuum permeability
double mub2mu0; // prefactor for mech force
double mub2mu0hbinv; // prefactor for mag force
void set_grid_global();
double newton_raphson_f();
@ -72,7 +77,7 @@ class PPPMSpin : public PPPM {
class GridComm *cg_spin;
class GridComm *cg_peratom_spin;
int only_spin_flag;
double musum,musqsum,mu2;
double spsum,spsqsum,sp2;
double find_gewald_spin(double, double, bigint, double, double);
double newton_raphson_f_spin(double, double, bigint, double, double);
double derivf_spin(double, double, bigint, double, double);
@ -86,7 +91,7 @@ class PPPMSpin : public PPPM {
void fieldforce_ik_spin();
void fieldforce_peratom_spin();
double final_accuracy_spin();
void musum_musq();
void spsum_spsq();
};

2
src/SPIN/pair_spin_long.cpp
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@ -59,7 +59,7 @@ PairSpinLong::PairSpinLong(LAMMPS *lmp) : PairSpin(lmp),
lockfixnvespin(NULL)
{
single_enable = 0;
ewaldflag = pppmflag = 1;
ewaldflag = pppmflag = spinflag = 1;
respa_enable = 0;
no_virial_fdotr_compute = 1;
lattice_flag = 0;

4
src/kspace.cpp
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@ -37,7 +37,7 @@ KSpace::KSpace(LAMMPS *lmp, int narg, char **arg) : Pointers(lmp)
virial[0] = virial[1] = virial[2] = virial[3] = virial[4] = virial[5] = 0.0;
triclinic_support = 1;
ewaldflag = pppmflag = msmflag = dispersionflag = tip4pflag = dipoleflag = 0;
ewaldflag = pppmflag = msmflag = dispersionflag = tip4pflag = dipoleflag = spinflag = 0;
compute_flag = 1;
group_group_enable = 0;
stagger_flag = 0;
@ -192,6 +192,8 @@ void KSpace::pair_check()
error->all(FLERR,"KSpace style is incompatible with Pair style");
if (dipoleflag && !force->pair->dipoleflag)
error->all(FLERR,"KSpace style is incompatible with Pair style");
if (spinflag && !force->pair->spinflag)
error->all(FLERR,"KSpace style is incompatible with Pair style");
if (tip4pflag && !force->pair->tip4pflag)
error->all(FLERR,"KSpace style is incompatible with Pair style");

1
src/kspace.h
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@ -44,6 +44,7 @@ class KSpace : protected Pointers {
int dispersionflag; // 1 if a LJ/dispersion solver
int tip4pflag; // 1 if a TIP4P solver
int dipoleflag; // 1 if a dipole solver
int spinflag; // 1 if a spin solver
int differentiation_flag;
int neighrequest_flag; // used to avoid obsolete construction
// of neighbor lists

2
src/pair.cpp
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@ -72,7 +72,7 @@ Pair::Pair(LAMMPS *lmp) : Pointers(lmp)
single_extra = 0;
svector = NULL;
ewaldflag = pppmflag = msmflag = dispersionflag = tip4pflag = dipoleflag = 0;
ewaldflag = pppmflag = msmflag = dispersionflag = tip4pflag = dipoleflag = spinflag = 0;
reinitflag = 1;
// pair_modify settings

1
src/pair.h
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@ -61,6 +61,7 @@ class Pair : protected Pointers {
int dispersionflag; // 1 if compatible with LJ/dispersion solver
int tip4pflag; // 1 if compatible with TIP4P solver
int dipoleflag; // 1 if compatible with dipole solver
int spinflag; // 1 if compatible with spin long solver
int reinitflag; // 1 if compatible with fix adapt and alike
int tail_flag; // pair_modify flag for LJ tail correction

1
src/pair_hybrid.cpp
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@ -352,6 +352,7 @@ void PairHybrid::flags()
if (styles[m]->pppmflag) pppmflag = 1;
if (styles[m]->msmflag) msmflag = 1;
if (styles[m]->dipoleflag) dipoleflag = 1;
if (styles[m]->spinflag) spinflag = 1;
if (styles[m]->dispersionflag) dispersionflag = 1;
if (styles[m]->tip4pflag) tip4pflag = 1;
if (styles[m]->compute_flag) compute_flag = 1;