diff --git a/rmgpy/rmgobject.pyx b/rmgpy/rmgobject.pyx
index 61e43ae2103..dd3a459d2f0 100644
--- a/rmgpy/rmgobject.pyx
+++ b/rmgpy/rmgobject.pyx
@@ -57,12 +57,11 @@ cdef class RMGObject(object):
         for key, val in output_dict.iteritems():
             if isinstance(val, list) and val and isinstance(val[0], RMGObject):
                 output_dict[key] = [v.as_dict() for v in val]
+            elif isinstance(val, np.ndarray):
+                output_dict[key] = val.tolist()
             elif not isinstance(val, (int, float, str, dict)) and val:
-                if isinstance(val, np.ndarray):
-                    output_dict[key] = val.tolist()
-                else:
-                    # this is an object, call as_dict() again
-                    output_dict[key] = val.as_dict()
+                # this is an object, call as_dict() again
+                output_dict[key] = val.as_dict()
         return output_dict
 
     cpdef make_object(self, dict data, dict class_dict):