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git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@2044 f3b2605a-c512-4ea7-a41b-209d697bcdaa

This commit is contained in:
sjplimp 2008-08-11 17:47:40 +00:00
parent 98fc490061
commit 612d47f4a7
2 changed files with 17 additions and 39 deletions
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55
src/MANYBODY/pair_tersoff.cpp
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@ -474,6 +474,10 @@ void PairTersoff::read_file(char *file)
params[nparams].lam1 = atof(words[15]);
params[nparams].biga = atof(words[16]);
// currently only allow m exponent of 1 or 3
params[nparams].powermint = int(params[nparams].powerm);
if (
params[nparams].lam3 < 0.0 || params[nparams].c < 0.0 ||
params[nparams].d < 0.0 || params[nparams].powern < 0.0 ||
@ -482,8 +486,9 @@ void PairTersoff::read_file(char *file)
params[nparams].bigd < 0.0 ||
params[nparams].bigd > params[nparams].bigr ||
params[nparams].lam3 < 0.0 || params[nparams].biga < 0.0 ||
params[nparams].powerm - int(params[nparams].powerm) != 0.0 ||
params[nparams].powerm < 0.0 || params[nparams].gamma < 0.0)
params[nparams].powerm - params[nparams].powermint != 0.0 ||
(params[nparams].powermint != 3 && params[nparams].powermint != 1) ||
params[nparams].gamma < 0.0)
error->all("Illegal Tersoff parameter");
nparams++;
@ -568,7 +573,9 @@ double PairTersoff::zeta(Param *param, double rsqij, double rsqik,
costheta = (delrij[0]*delrik[0] + delrij[1]*delrik[1] +
delrij[2]*delrik[2]) / (rij*rik);
arg = pow(param->lam3 * (rij-rik),param->powerm);
if (param->powermint == 3) arg = pow(param->lam3 * (rij-rik),3.0);
else arg = param->lam3 * (rij-rik);
if (arg > 69.0776) ex_delr = 1.e30;
else if (arg < -69.0776) ex_delr = 0.0;
else ex_delr = exp(arg);
@ -725,14 +732,17 @@ void PairTersoff::ters_zetaterm_d(double prefactor,
fc = ters_fc(rik,param);
dfc = ters_fc_d(rik,param);
tmp = pow(param->lam3 * (rij-rik),param->powerm);
if (param->powermint == 3) tmp = pow(param->lam3 * (rij-rik),3.0);
else tmp = param->lam3 * (rij-rik);
if (tmp > 69.0776) ex_delr = 1.e30;
else if (tmp < -69.0776) ex_delr = 0.0;
else ex_delr = exp(tmp);
ex_delr_d = (param->powerm*pow(param->lam3,param->powerm)) *
pow(rij-rik,param->powerm-1.0)*ex_delr;
if (param->powermint == 3)
ex_delr_d = 3.0*pow(param->lam3,3.0) * pow(rij-rik,2.0)*ex_delr;
else ex_delr_d = param->lam3 * ex_delr;
cos_theta = vec3_dot(rij_hat,rik_hat);
gijk = ters_gijk(cos_theta,param);
gijk_d = ters_gijk_d(cos_theta,param);
@ -785,36 +795,3 @@ void PairTersoff::costheta_d(double *rij_hat, double rij,
vec3_add(drj,drk,dri);
vec3_scale(-1.0,dri,dri);
};
/* ----------------------------------------------------------------------
vector routines
------------------------------------------------------------------------- */
/*
double PairTersoff::vec3_dot(double *x, double *y)
{
return x[0]*y[0] + x[1]*y[1] + x[2]*y[2];
}
void PairTersoff::vec3_add(double *x, double *y, double *z)
{
z[0] = x[0]+y[0];
z[1] = x[1]+y[1];
z[2] = x[2]+y[2];
}
void PairTersoff::vec3_scale(double k, double *x, double *y)
{
y[0] = k*x[0];
y[1] = k*x[1];
y[2] = k*x[2];
}
void PairTersoff::vec3_scaleadd(double k, double *x, double *y, double *z)
{
z[0] = k*x[0]+y[0];
z[1] = k*x[1]+y[1];
z[2] = k*x[2]+y[2];
}
*/

1
src/MANYBODY/pair_tersoff.h
View File

@ -38,6 +38,7 @@ class PairTersoff : public Pair {
double cut,cutsq;
double c1,c2,c3,c4;
int ielement,jelement,kelement;
int powermint;
};
double PI2,PI4;