diff --git a/nomad/datamodel/metainfo/basesections.py b/nomad/datamodel/metainfo/basesections.py
index 942a6aecc0559ce1e35fa8a4c2837cff0ce2f45a..61cfa1014d25a759988728bcbbdefceb01d1db65 100644
--- a/nomad/datamodel/metainfo/basesections.py
+++ b/nomad/datamodel/metainfo/basesections.py
@@ -1129,7 +1129,7 @@ class CompositeSystem(System):
                         elemental_composition = elemental_composition_from_formula(
                             formula
                         )
-                    except ValueError:
+                    except (AttributeError, ValueError):
                         elemental_composition = []
                 elif isinstance(component, SystemComponent):
                     elemental_composition = component.system.elemental_composition