--- trunk/OOPSE/libmdtools/SimInfo.cpp	2003/04/04 19:47:19	458
+++ trunk/OOPSE/libmdtools/SimInfo.cpp	2003/04/05 03:39:25	463
@@ -35,10 +35,56 @@ void SimInfo::setBox(double newBox[3]) {
 }
 
 void SimInfo::setBox(double newBox[3]) {
+  double smallestBox, maxCutoff;
+  int status;
   box_x = newBox[0];
   box_y = newBox[1];
   box_z = newBox[2];
   setFortranBoxSize(newBox);
+
+  smallestBox = box_x;
+  if (box_y < smallestBox) smallestBox = box_y;
+  if (box_z < smallestBox) smallestBox = box_z;
+
+  maxCutoff = smallestBox / 2.0;
+
+  if (rList > maxCutoff) {
+    sprintf( painCave.errMsg,
+             "New Box size is forcing neighborlist radius down to %lf\n",
+             maxCutoff );
+    painCave.isFatal = 0;
+    simError();
+
+    rList = maxCutoff;
+
+    sprintf( painCave.errMsg,
+             "New Box size is forcing cutoff radius down to %lf\n",
+             maxCutoff - 1.0 );
+    painCave.isFatal = 0;
+    simError();
+
+    rCut = rList - 1.0;
+
+    // list radius changed so we have to refresh the simulation structure.
+    refreshSim();
+  }
+
+  if (rCut > maxCutoff) {
+    sprintf( painCave.errMsg,
+             "New Box size is forcing cutoff radius down to %lf\n",
+             maxCutoff );
+    painCave.isFatal = 0;
+    simError();
+
+    status = 0;
+    LJ_new_rcut(&rCut, &status);
+    if (status != 0) {
+      sprintf( painCave.errMsg,
+               "Error in recomputing LJ shifts based on new rcut\n");
+      painCave.isFatal = 1;
+      simError();
+    }
+  }
 }
 
 void SimInfo::getBox(double theBox[3]) {