X-Git-Url: https://hackdaworld.org/gitweb/?a=blobdiff_plain;f=potentials%2Flennard_jones.c;h=4ff1b4371eb95dc496a66257c993f88786f25724;hb=684bf7c398cdfa98549b0c7a1fa37e6dc5b35bea;hp=1738ea547c0e8600a4f0c8a6f06d8c2cd026a9b1;hpb=296a35b943e922173ce648ec76a4472e287af108;p=physik%2Fposic.git

diff --git a/potentials/lennard_jones.c b/potentials/lennard_jones.c
index 1738ea5..4ff1b43 100644
--- a/potentials/lennard_jones.c
+++ b/potentials/lennard_jones.c
@@ -25,6 +25,7 @@ int lennard_jones(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
 	t_3dvec force,distance;
 	double d,h1,h2;
 	double eps,sig6,sig12;
+	double energy;
 
 	params=moldyn->pot_params;
 	eps=params->epsilon4;
@@ -35,12 +36,16 @@ int lennard_jones(t_moldyn *moldyn,t_atom *ai,t_atom *aj,u8 bc) {
 
 	v3_sub(&distance,&(aj->r),&(ai->r));
 	if(bc) check_per_bound(moldyn,&distance);
-	d=v3_absolute_square(&distance);	/* 1/r^2 */
+	d=v3_absolute_square(&distance);	/* r^2 */
 	if(d<=moldyn->cutoff_square) {
 		d=1.0/d; 			/* 1/r^2 */
 		h2=d*d;				/* 1/r^4 */
+		h2*=d;				/* 1/r^6 */
 		h1=h2*h2;			/* 1/r^12 */
-		moldyn->energy+=(eps*(sig12*h1-sig6*h2)-params->uc);
+		energy=(eps*(sig12*h1-sig6*h2)-params->uc);
+		moldyn->energy+=energy;		/* total energy */
+		ai->e+=0.5*energy;		/* site energy */
+		aj->e+=0.5*energy;
 		h2*=d;				/* 1/r^8 */
 		h1*=d;				/* 1/r^14 */
 		h2*=6*sig6;