diff --git a/trunk/lattice.f90 b/trunk/lattice.f90
index 417c4a68a..cb532173b 100644
--- a/trunk/lattice.f90
+++ b/trunk/lattice.f90
@@ -723,7 +723,7 @@ function lattice_initializeStructure(struct,CoverA)
        interactionSlipSlip => lattice_hex_interactionSlipSlip
        interactionSlipTwin => lattice_hex_interactionSlipTwin
        interactionTwinTwin => lattice_hex_interactionTwinTwin
-       interactionTwinTwin => lattice_hex_interactionTwinSlip
+       interactionTwinSlip => lattice_hex_interactionTwinSlip
      endif
    end select