diff --git a/Resample/Particle/ReParticle.h b/Resample/Particle/ReParticle.h
index 6bfd0c19e9a746241389206bda60b0f6b3b41eb7..bd8feb42303b2eb5c70a697588bb66cc0d1bc269 100644
--- a/Resample/Particle/ReParticle.h
+++ b/Resample/Particle/ReParticle.h
@@ -59,15 +59,14 @@ public:
     virtual complex_t formfactor_at_bottom(C3 q) const;
 
 private:
-    std::unique_ptr<const IFormFactor> m_ff;
+    const std::unique_ptr<const IFormFactor> m_ff;
+    std::unique_ptr<const Material> m_material;
+    std::unique_ptr<const Material> m_ambient_material;
+    const std::unique_ptr<const R3> m_position;
+    const std::unique_ptr<const RotMatrix> m_rotMatrix;
 
     ReParticle(const std::optional<size_t>& i_layer, IFormFactor* ff, const Material* material,
                const Material* ambient_material, const R3* position, const RotMatrix* rotMatrix);
-
-    std::unique_ptr<const Material> m_material;
-    std::unique_ptr<const Material> m_ambient_material;
-    std::unique_ptr<const R3> m_position;
-    std::unique_ptr<const RotMatrix> m_rotMatrix;
 };
 
 #endif // BORNAGAIN_RESAMPLE_PARTICLE_REPARTICLE_H