diff --git a/ocaml/Angmom.ml b/ocaml/Angmom.ml
index 4e315a95..0f1658f0 100644
--- a/ocaml/Angmom.ml
+++ b/ocaml/Angmom.ml
@@ -2,6 +2,7 @@ open Qptypes
 open Sexplib.Std
 
 type t = S|P|D|F|G|H|I|J|K|L [@@deriving sexp]
+type st = t [@@deriving sexp]
 
 let to_string = function
   | S -> "S"
@@ -70,9 +71,6 @@ let of_l i =
   | x -> raise (Failure ("Angmom should be S|P|D|F|G|H|I|J|K|L"))
 
 
-type st = t
-
-
 module Xyz = struct
   type t = { x: Positive_int.t ;
              y: Positive_int.t ;