diff --git a/src/fenicsxconcrete/finite_element_problem/concrete_thermo_mechanical.py b/src/fenicsxconcrete/finite_element_problem/concrete_thermo_mechanical.py
index a6f610f..0fbfc75 100644
--- a/src/fenicsxconcrete/finite_element_problem/concrete_thermo_mechanical.py
+++ b/src/fenicsxconcrete/finite_element_problem/concrete_thermo_mechanical.py
@@ -113,7 +113,7 @@ def default_parameters() -> tuple[Experiment, dict[str, pint.Quantity]]:
             "dt": 1.0 * ureg("s"),
         }
         default_parameters["E_act"] = (
-            5653.0 * default_parameters["igc"].magnitude * ureg("J/mol")
+            5653.0 * ureg("K") * default_parameters["igc"] 
         )  # TODO Check with Sjard
 
         return experiment, default_parameters