diff --git a/diffusivityModel/Particle/Particle.C b/diffusivityModel/Particle/Particle.C
index c2f21de..aa6120c 100644
--- a/diffusivityModel/Particle/Particle.C
+++ b/diffusivityModel/Particle/Particle.C
@@ -78,37 +78,52 @@ Foam::Particle::Particle(const dictionary& thermoDict, const dictionary& tranDic
     Zrot_(tranDict.lookupOrDefault("rotationalRelaxation", 0.0)),
     thermo_(thermoDict)
 {
-    label geometry = 0;
-
     const entry* entryPtr = tranDict.lookupEntryPtr("tranlib", false, true);
 
     if (entryPtr)
     {
         scalarList tranlib(entryPtr->stream());
-        geometry = tranlib[0];
+        label geometry = tranlib[0];
+
+        switch(geometry)
+        {
+            case 0:
+                geometry_ = Geometry::ATOM;
+                break;
+            case 1:
+                geometry_ = Geometry::LINEAR;
+                break;
+            case 2:
+                geometry_ = Geometry::NONLINEAR;
+                break;
+            default:
+                FatalErrorInFunction
+                    << "Illegal molecule geometry type. 0, 1 and 2 are allowed."
+                    << abort(FatalError);
+        }
     }
     else
     {
-        geometry = readLabel(tranDict.lookup("geometry"));
-    }
-
-    switch(geometry)
-    {
-        case 0:
-            geometry_ = Geometry::ATOM;
-            break;
-        case 1:
-            geometry_ = Geometry::LINEAR;
-            break;
-        case 2:
-            geometry_ = Geometry::NONLINEAR;
-            break;
-        default:
+        word gWord(tranDict.lookup("geometry"));
+        if (gWord == "atom")
+        {
+                geometry_ = Geometry::ATOM;
+        }
+        else if (gWord == "linear")
+        {
+                geometry_ = Geometry::LINEAR;
+        }
+        else if (gWord == "nonlinear")
+        {
+                geometry_ = Geometry::NONLINEAR;
+        }
+        else
+        {
             FatalErrorInFunction
-                << "Illegal molecule geometry type. 0, 1 and 2 are allowed."
+                << "Illegal molecule geometry type. atom, linear and nonlinear are allowed."
                 << abort(FatalError);
+        }
     }
-
 }