diff --git a/doc/source/scripts/gen_topologyattr_defaults.py b/doc/source/scripts/gen_topologyattr_defaults.py
index 4e507150..250cecad 100644
--- a/doc/source/scripts/gen_topologyattr_defaults.py
+++ b/doc/source/scripts/gen_topologyattr_defaults.py
@@ -23,10 +23,10 @@
 class TopologyDefaults:
     def __init__(self) -> None:
         def _atom(klass: TopologyAttr) -> str:
-            return klass.attrname  # type: ignore
+            return klass.singular  # type: ignore
 
         def _atomgroup(klass: TopologyAttr) -> str:
-            return klass.singular  # type: ignore
+            return klass.attrname  # type: ignore
 
         def _default(klass: TopologyAttr) -> str:
             try: