#include "tersoff.h"
/* create mixed terms from parameters and set them */
-int tersoff_mult_complete_params(t_tersoff_mult_params *p) {
+int tersoff_mult_set_params(t_moldyn *moldyn,int element1,int element2) {
- printf("[moldyn] tersoff parameter completion\n");
+ t_tersoff_mult_params *p;
+
+ // set cutoff before parameters (actually only necessary for some pots)
+ if(moldyn->cutoff==0.0) {
+ printf("[tersoff] WARNING: no cutoff!\n");
+ return -1;
+ }
+
+ /* alloc mem for potential parameters */
+ moldyn->pot_params=malloc(sizeof(t_tersoff_mult_params));
+ if(moldyn->pot_params==NULL) {
+ perror("[tersoff] pot params alloc");
+ return -1;
+ }
+
+ /* these are now tersoff parameters */
+ p=moldyn->pot_params;
+
+ // only 1 combination by now :p
+ switch(element1) {
+ case SI:
+ /* type: silicon */
+ p->S[0]=TM_S_SI;
+ p->R[0]=TM_R_SI;
+ p->A[0]=TM_A_SI;
+ p->B[0]=TM_B_SI;
+ p->lambda[0]=TM_LAMBDA_SI;
+ p->mu[0]=TM_MU_SI;
+ p->beta[0]=TM_BETA_SI;
+ p->n[0]=TM_N_SI;
+ p->c[0]=TM_C_SI;
+ p->d[0]=TM_D_SI;
+ p->h[0]=TM_H_SI;
+ switch(element2) {
+ case C:
+ p->chi=TM_CHI_SIC;
+ break;
+ default:
+ printf("[tersoff] WARNING: element2\n");
+ return -1;
+ }
+ break;
+ default:
+ printf("[tersoff] WARNING: element1\n");
+ return -1;
+ }
+
+ switch(element2) {
+ case C:
+ /* type carbon */
+ p->S[1]=TM_S_C;
+ p->R[1]=TM_R_C;
+ p->A[1]=TM_A_C;
+ p->B[1]=TM_B_C;
+ p->lambda[1]=TM_LAMBDA_C;
+ p->mu[1]=TM_MU_C;
+ p->beta[1]=TM_BETA_C;
+ p->n[1]=TM_N_C;
+ p->c[1]=TM_C_C;
+ p->d[1]=TM_D_C;
+ p->h[1]=TM_H_C;
+ break;
+ default:
+ printf("[tersoff] WARNING: element2\n");
+ return -1;
+ }
+
+ printf("[tersoff] parameter completion\n");
p->S2[0]=p->S[0]*p->S[0];
p->S2[1]=p->S[1]*p->S[1];
- p->Smixed=sqrt(p->S[0]*p->S[1]);
- p->S2mixed=p->Smixed*p->Smixed;
+ p->S2mixed=p->S[0]*p->S[1];
+ p->Smixed=sqrt(p->S2mixed);
p->Rmixed=sqrt(p->R[0]*p->R[1]);
p->Amixed=sqrt(p->A[0]*p->A[1]);
p->Bmixed=sqrt(p->B[0]*p->B[1]);
p->lambda_m=0.5*(p->lambda[0]+p->lambda[1]);
p->mu_m=0.5*(p->mu[0]+p->mu[1]);
-
- printf("[moldyn] tersoff mult parameter info:\n");
+ p->betaini[0]=pow(p->beta[0],p->n[0]);
+ p->betaini[1]=pow(p->beta[1],p->n[1]);
+ p->ci2[0]=p->c[0]*p->c[0];
+ p->ci2[1]=p->c[1]*p->c[1];
+ p->di2[0]=p->d[0]*p->d[0];
+ p->di2[1]=p->d[1]*p->d[1];
+ p->ci2di2[0]=p->ci2[0]/p->di2[0];
+ p->ci2di2[1]=p->ci2[1]/p->di2[1];
+
+ printf("[tersoff] mult parameter info:\n");
printf(" S (A) | %f | %f | %f\n",p->S[0],p->S[1],p->Smixed);
printf(" R (A) | %f | %f | %f\n",p->R[0],p->R[1],p->Rmixed);
printf(" A (eV) | %f | %f | %f\n",p->A[0]/EV,p->A[1]/EV,p->Amixed/EV);
return 0;
}
-/* tersoff 1 body part */
-int tersoff_mult_1bp(t_moldyn *moldyn,t_atom *ai) {
-
- int brand;
- t_tersoff_mult_params *params;
- t_tersoff_exchange *exchange;
-
- brand=ai->brand;
- params=moldyn->pot_params;
- exchange=&(params->exchange);
-
- /*
- * simple: point constant parameters only depending on atom i to
- * their right values
- */
-
- exchange->beta_i=&(params->beta[brand]);
- exchange->n_i=&(params->n[brand]);
- exchange->c_i=&(params->c[brand]);
- exchange->d_i=&(params->d[brand]);
- exchange->h_i=&(params->h[brand]);
-
- exchange->betaini=pow(*(exchange->beta_i),*(exchange->n_i));
- exchange->ci2=params->c[brand]*params->c[brand];
- exchange->di2=params->d[brand]*params->d[brand];
- exchange->ci2di2=exchange->ci2/exchange->di2;
-
- return 0;
-}
-
/* tersoff 2 body part */
int tersoff_mult_2bp(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
int brand;
double s_r;
double arg;
+ double energy;
+
+ printf("WARNING! - tersoff_mult_2bp is obsolete.\n");
+ printf("WARNING! - repulsive part handled in 3bp/j2 routine.\n");
/* use newtons third law */
if(ai<aj) return 0;
/* add forces */
v3_add(&(ai->f),&(ai->f),&force);
- v3_sub(&(aj->f),&(aj->f),&force);
+ v3_scale(&force,&force,-1.0); // reason: dri rij = - drj rij
+ v3_add(&(aj->f),&(aj->f),&force);
#ifdef DEBUG
if((ai==&(moldyn->atom[0]))|(aj==&(moldyn->atom[0]))) {
#endif
/* virial */
- //virial_calc(ai,&force,&dist_ij);
- //virial_calc(aj,&force,&dist_ij);
- //ai->virial.xx-=force.x*dist_ij.x;
- //ai->virial.yy-=force.y*dist_ij.y;
- //ai->virial.zz-=force.z*dist_ij.z;
- //ai->virial.xy-=force.x*dist_ij.y;
- //ai->virial.xz-=force.x*dist_ij.z;
- //ai->virial.yz-=force.y*dist_ij.z;
+ virial_calc(ai,&force,&dist_ij);
/* energy 2bp contribution */
- moldyn->energy+=f_r*f_c;
+ energy=f_r*f_c;
+ moldyn->energy+=energy;
+ ai->e+=0.5*energy;
+ aj->e+=0.5*energy;
return 0;
}
cos_theta=v3_scalar_product(&dist_ij,&dist_ik)/(d_ij*d_ik);
/* g_ijk */
- h_cos=*(exchange->h_i)-cos_theta;
- d2_h_cos2=exchange->di2+(h_cos*h_cos);
- frac=exchange->ci2/d2_h_cos2;
- g=1.0+exchange->ci2di2-frac;
+ h_cos=params->h[brand]-cos_theta;
+ d2_h_cos2=params->di2[brand]+(h_cos*h_cos);
+ frac=params->ci2[brand]/d2_h_cos2;
+ g=1.0+params->ci2di2[brand]-frac;
dg=-2.0*frac*h_cos/d2_h_cos2;
/* zeta sum += f_c_ik * g_ijk */
exchange->zeta_ij+=f_c_ik*g;
}
+#ifdef DEBUG
+ if(ai==&(moldyn->atom[DATOM]))
+ printf("zeta_ij: %f %f %f %f\n",f_c_ik*g,f_c_ik,g,d_ik);
+#endif
+
/* store even more data for second k loop */
exchange->g[kcount]=g;
exchange->dg[kcount]=dg;
t_tersoff_exchange *exchange;
t_3dvec force;
double f_a,df_a,b,db,f_c,df_c;
+ double f_r,df_r;
+ double scale;
double mu,B,chi;
+ double lambda,A;
double d_ij;
unsigned char brand;
double ni,tmp;
double S,R,s_r,arg;
+ double energy;
params=moldyn->pot_params;
exchange=&(params->exchange);
- brand=aj->brand;
- if(brand==ai->brand) {
+ brand=ai->brand;
+ if(brand==aj->brand) {
S=params->S[brand];
R=params->R[brand];
B=params->B[brand];
+ A=params->A[brand];
mu=params->mu[brand];
+ lambda=params->lambda[brand];
chi=1.0;
}
else {
S=params->Smixed;
R=params->Rmixed;
B=params->Bmixed;
+ A=params->Amixed;
mu=params->mu_m;
+ lambda=params->lambda_m;
chi=params->chi;
}
f_a=-B*exp(-mu*d_ij);
df_a=mu*f_a/d_ij;
+ /* f_r, df_r */
+ f_r=A*exp(-lambda*d_ij);
+ df_r=lambda*f_r/d_ij;
+
/* b, db */
if(exchange->zeta_ij==0.0) {
b=chi;
db=0.0;
}
else {
- ni=*(exchange->n_i);
- tmp=exchange->betaini*pow(exchange->zeta_ij,ni-1.0);
+ ni=params->n[brand];
+ tmp=params->betaini[brand]*pow(exchange->zeta_ij,ni-1.0);
b=(1.0+exchange->zeta_ij*tmp);
- db=chi*pow(b,-1.0/(2*ni)-1.0);
+ db=chi*pow(b,-1.0/(2.0*ni)-1.0);
b=db*b;
db*=-0.5*tmp;
}
/* force contribution */
- v3_scale(&force,&(exchange->dist_ij),df_a*f_c+f_a*df_c);
- v3_scale(&force,&force,-0.5*b);
+ scale=-0.5*(f_c*(df_r+b*df_a)+df_c*(f_r+b*df_a));
+ v3_scale(&force,&(exchange->dist_ij),scale);
v3_add(&(ai->f),&(ai->f),&force);
- v3_sub(&(aj->f),&(aj->f),&force);
+ v3_scale(&force,&force,-1.0); // dri rij = - drj rij
+ v3_add(&(aj->f),&(aj->f),&force);
#ifdef DEBUG
- if((ai==&(moldyn->atom[0]))|(aj==&(moldyn->atom[0]))) {
+ if((ai==&(moldyn->atom[DATOM]))|(aj==&(moldyn->atom[DATOM]))) {
printf("force 3bp (j2): [%d %d sum]\n",ai->tag,aj->tag);
printf("adding %f %f %f\n",force.x,force.y,force.z);
- if(ai==&(moldyn->atom[0]))
+ if(ai==&(moldyn->atom[DATOM]))
printf("total i: %f %f %f\n",ai->f.x,ai->f.y,ai->f.z);
- if(aj==&(moldyn->atom[0]))
+ if(aj==&(moldyn->atom[DATOM]))
printf("total j: %f %f %f\n",aj->f.x,aj->f.y,aj->f.z);
+ printf("energy: %f = %f %f %f %f\n",0.5*f_c*(b*f_a+f_r),
+ f_c,b,f_a,f_r);
+ printf(" %f %f %f\n",exchange->zeta_ij,.0,.0);
}
#endif
/* virial */
- //virial_calc(ai,&force,&(exchange->dist_ij));
- //virial_calc(aj,&force,&(exchange->dist_ij));
+ virial_calc(ai,&force,&(exchange->dist_ij));
/* dzeta prefactor = - 0.5 f_c f_a db */
exchange->pre_dzeta=-0.5*f_a*f_c*db;
/* energy contribution */
- moldyn->energy+=0.5*f_c*b*f_a;
+ energy=0.5*f_c*(b*f_a+f_r);
+ moldyn->energy+=energy;
+ ai->e+=energy;
/* reset k counter for second k loop */
exchange->kcount=0;
double pre_dzeta;
double f_c_ik,df_c_ik;
double dijdik_inv,fcdg,dfcg;
- t_3dvec dcosdri,dcosdrj,dcosdrk;
+ t_3dvec dcosdrj,dcosdrk;
t_3dvec force,tmp;
params=moldyn->pot_params;
v3_scale(&dcosdrk,&dist_ij,dijdik_inv);
v3_scale(&tmp,&dist_ik,-cos_theta/d_ik2);
v3_add(&dcosdrk,&dcosdrk,&tmp);
- v3_add(&dcosdri,&dcosdrj,&dcosdrk);
- v3_scale(&dcosdri,&dcosdri,-1.0);
/* f_c_ik * dg, df_c_ik * g */
fcdg=f_c_ik*dg;
dfcg=df_c_ik*g;
- /* derivative wrt i */
- v3_scale(&force,&dist_ik,dfcg);
- v3_scale(&tmp,&dcosdri,fcdg);
- v3_add(&force,&force,&tmp);
- v3_scale(&force,&force,pre_dzeta);
-
- /* force contribution */
- v3_add(&(ai->f),&(ai->f),&force);
-
-#ifdef DEBUG
- if(ai==&(moldyn->atom[0])) {
- printf("force 3bp (k2): [%d %d %d]\n",ai->tag,aj->tag,ak->tag);
- printf("adding %f %f %f\n",force.x,force.y,force.z);
- printf("total i: %f %f %f\n",ai->f.x,ai->f.y,ai->f.z);
- }
-#endif
-
- /* virial */
- //virial_calc(ai,&force,&dist_ij);
-
- /* derivatice wrt j */
+ /* derivative wrt j */
v3_scale(&force,&dcosdrj,fcdg*pre_dzeta);
/* force contribution */
v3_add(&(aj->f),&(aj->f),&force);
#ifdef DEBUG
- if(aj==&(moldyn->atom[0])) {
+ if(aj==&(moldyn->atom[DATOM])) {
printf("force 3bp (k2): [%d %d %d]\n",ai->tag,aj->tag,ak->tag);
- printf("adding %f %f %f\n",force.x,force.y,force.z);
- printf("total j: %f %f %f\n",aj->f.x,aj->f.y,aj->f.z);
+ printf(" adding %f %f %f\n",force.x,force.y,force.z);
+ printf(" total j: %f %f %f\n",aj->f.x,aj->f.y,aj->f.z);
+ printf(" angle: %f\n",acos(cos_theta)*360.0/(2*M_PI));
+ printf(" d ij ik = %f %f\n",d_ij,d_ik);
}
#endif
/* virial */
- //virial_calc(aj,&force,&dist_ij);
+ virial_calc(ai,&force,&dist_ij);
+
+ /* force contribution to atom i */
+ v3_scale(&force,&force,-1.0);
+ v3_add(&(ai->f),&(ai->f),&force);
/* derivative wrt k */
- v3_scale(&force,&dist_ik,dfcg);
+ v3_scale(&force,&dist_ik,-1.0*dfcg); // dri rik = - drk rik
v3_scale(&tmp,&dcosdrk,fcdg);
v3_add(&force,&force,&tmp);
v3_scale(&force,&force,pre_dzeta);
v3_add(&(ak->f),&(ak->f),&force);
#ifdef DEBUG
- if(ak==&(moldyn->atom[0])) {
+ if(ak==&(moldyn->atom[DATOM])) {
printf("force 3bp (k2): [%d %d %d]\n",ai->tag,aj->tag,ak->tag);
- printf("adding %f %f %f\n",force.x,force.y,force.z);
- printf("total k: %f %f %f\n",ak->f.x,ak->f.y,ak->f.z);
+ printf(" adding %f %f %f\n",force.x,force.y,force.z);
+ printf(" total k: %f %f %f\n",ak->f.x,ak->f.y,ak->f.z);
+ printf(" angle: %f\n",acos(cos_theta)*360.0/(2*M_PI));
+ printf(" d ij ik = %f %f\n",d_ij,d_ik);
}
#endif
/* virial */
- virial_calc(ak,&force,&dist_ik);
+ virial_calc(ai,&force,&dist_ik);
+
+ /* force contribution to atom i */
+ v3_scale(&force,&force,-1.0);
+ v3_add(&(ai->f),&(ai->f),&force);
/* increase k counter */
- exchange->kcount++;
+ exchange->kcount++;
return 0;
}
+
+int tersoff_mult_check_2b_bond(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
+
+ t_tersoff_mult_params *params;
+ t_3dvec dist;
+ double d;
+ u8 brand;
+
+ v3_sub(&dist,&(aj->r),&(ai->r));
+ if(bc) check_per_bound(moldyn,&dist);
+ d=v3_absolute_square(&dist);
+
+ params=moldyn->pot_params;
+ brand=ai->brand;
+
+ if(brand==aj->brand) {
+ if(d<=params->S2[brand])
+ return TRUE;
+ }
+ else {
+ if(d<=params->S2mixed)
+ return TRUE;
+ }
+
+ return FALSE;
+}
+