X-Git-Url: https://hackdaworld.org/gitweb/?a=blobdiff_plain;f=potentials%2Ftersoff.c;h=b6533e19bf90c3709b5915198c6a2964be2efc41;hb=7fcb896467bdf236f60c4c3784a9d51214737fcb;hp=531d292131121ad5acb7b1ce2a4a0c551199b34a;hpb=0b96eb313c9bfec6272b1f8de0d99c4ce26d1686;p=physik%2Fposic.git

diff --git a/potentials/tersoff.c b/potentials/tersoff.c
index 531d292..b6533e1 100644
--- a/potentials/tersoff.c
+++ b/potentials/tersoff.c
@@ -153,7 +153,7 @@ int tersoff_mult_2bp(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
 
 	/* add forces */
 	v3_add(&(ai->f),&(ai->f),&force);
-	v3_sub(&(aj->f),&(aj->f),&force);
+	v3_sub(&(aj->f),&(aj->f),&force); // reason: dri rij = - drj rij
 
 #ifdef DEBUG
 	if((ai==&(moldyn->atom[0]))|(aj==&(moldyn->atom[0]))) {
@@ -388,7 +388,7 @@ int tersoff_mult_3bp_j2(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
 		ni=*(exchange->n_i);
 		tmp=exchange->betaini*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;
 	}
@@ -397,7 +397,7 @@ int tersoff_mult_3bp_j2(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
 	v3_scale(&force,&(exchange->dist_ij),df_a*f_c+f_a*df_c);
 	v3_scale(&force,&force,-0.5*b);
 	v3_add(&(ai->f),&(ai->f),&force);
-	v3_sub(&(aj->f),&(aj->f),&force);
+	v3_sub(&(aj->f),&(aj->f),&force); // dri rij = - drj rij
 
 #ifdef DEBUG
 	if((ai==&(moldyn->atom[0]))|(aj==&(moldyn->atom[0]))) {
@@ -522,7 +522,7 @@ int tersoff_mult_3bp_k2(t_moldyn *moldyn,
 	/* virial */
 	//virial_calc(ai,&force,&dist_ij);
 
-	/* derivatice wrt j */
+	/* derivative wrt j */
 	v3_scale(&force,&dcosdrj,fcdg*pre_dzeta);
 
 	/* force contribution */
@@ -540,7 +540,7 @@ int tersoff_mult_3bp_k2(t_moldyn *moldyn,
 	//virial_calc(aj,&force,&dist_ij);
 
 	/* derivative wrt k */
-	v3_scale(&force,&dist_ik,dfcg);
+	v3_scale(&force,&dist_ik,-1.0*dfcg); // dri rij = - drj rij
 	v3_scale(&tmp,&dcosdrk,fcdg);
 	v3_add(&force,&force,&tmp);
 	v3_scale(&force,&force,pre_dzeta);