--- trunk/src/primitives/Bend.cpp	2010/05/10 17:28:26	1442
+++ trunk/src/primitives/Bend.cpp	2013/12/05 18:19:26	1953
@@ -35,19 +35,22 @@
  *                                                                      
  * [1]  Meineke, et al., J. Comp. Chem. 26, 252-271 (2005).             
  * [2]  Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006).          
- * [3]  Sun, Lin & Gezelter, J. Chem. Phys. 128, 24107 (2008).          
- * [4]  Vardeman & Gezelter, in progress (2009).                        
+ * [3]  Sun, Lin & Gezelter, J. Chem. Phys. 128, 234107 (2008).          
+ * [4]  Kuang & Gezelter,  J. Chem. Phys. 133, 164101 (2010).
+ * [5]  Vardeman, Stocker & Gezelter, J. Chem. Theory Comput. 7, 834 (2011).
  */
  
+#include "config.h"
+#include <cmath>
 #include "primitives/Bend.hpp"
 
 namespace OpenMD {
   
   /**@todo still a lot left to improve*/
-  void Bend::calcForce(RealType& angle) {
-    Vector3d pos1 = atom1_->getPos();
-    Vector3d pos2 = atom2_->getPos();
-    Vector3d pos3 = atom3_->getPos();
+  void Bend::calcForce(RealType& angle, bool doParticlePot) {
+    Vector3d pos1 = atoms_[0]->getPos();
+    Vector3d pos2 = atoms_[1]->getPos();
+    Vector3d pos3 = atoms_[2]->getPos();
     
     Vector3d r21 = pos1 - pos2;
     RealType d21 = r21.length();
@@ -90,13 +93,15 @@ namespace OpenMD {
     Vector3d force2 = force1 + force3;
     force2 *= -1.0;
     
-    atom1_->addFrc(force1);
-    atom2_->addFrc(force2);
-    atom3_->addFrc(force3);
+    atoms_[0]->addFrc(force1);
+    atoms_[1]->addFrc(force2);
+    atoms_[2]->addFrc(force3);
 
-    atom1_->addParticlePot(potential_);
-    atom2_->addParticlePot(potential_);
-    atom3_->addParticlePot(potential_);
+    if (doParticlePot) {
+      atoms_[0]->addParticlePot(potential_);
+      atoms_[1]->addParticlePot(potential_);
+      atoms_[2]->addParticlePot(potential_);
+    }
    
     angle = theta /M_PI * 180.0;
   }