--- branches/development/src/nonbonded/Sticky.cpp	2010/10/03 22:18:59	1505
+++ branches/development/src/nonbonded/Sticky.cpp	2011/04/08 21:25:19	1545
@@ -186,13 +186,12 @@ namespace OpenMD {
    * idat structure.
    */
   
-  void Sticky::calcForce(InteractionData idat) {
+  void Sticky::calcForce(InteractionData &idat) {
    
     if (!initialized_) initialize();
     
-    pair<AtomType*, AtomType*> key = make_pair(idat.atype1, idat.atype2);
     map<pair<AtomType*, AtomType*>, StickyInteractionData>::iterator it;
-    it = MixingMap.find(key);
+    it = MixingMap.find(idat.atypes);
     if (it != MixingMap.end()) {
 
       StickyInteractionData mixer = (*it).second;
@@ -343,8 +342,8 @@ namespace OpenMD {
           dspdr = 0.0;
         }
         
-        idat.vpair += 0.5*(v0*s*w + v0p*sp*wp);
-        idat.pot += 0.5*(v0*s*w + v0p*sp*wp)*idat.sw;
+        idat.vpair[2] += 0.5*(v0*s*w + v0p*sp*wp);
+        idat.pot[2] += 0.5*(v0*s*w + v0p*sp*wp)*idat.sw;
         
         // do the torques first since they are easy:
         // remember that these are still in the body-fixed axes
@@ -378,11 +377,10 @@ namespace OpenMD {
     return;      
   }
 
-  RealType Sticky::getSuggestedCutoffRadius(AtomType* at1, AtomType* at2) {
+  RealType Sticky::getSuggestedCutoffRadius(pair<AtomType*, AtomType*> atypes) {
     if (!initialized_) initialize();   
-    pair<AtomType*, AtomType*> key = make_pair(at1, at2); 
     map<pair<AtomType*, AtomType*>, StickyInteractionData>::iterator it;
-    it = MixingMap.find(key);
+    it = MixingMap.find(atypes);
     if (it == MixingMap.end()) 
       return 0.0;
     else  {