diff --git a/PuReMD/src/reax_types.h b/PuReMD/src/reax_types.h
index 9222c65e778c3b4124ce7e06f7399c7ab638cdad..2c282772a2df8cb0aea17e37d63cf8763a3f8662 100644
--- a/PuReMD/src/reax_types.h
+++ b/PuReMD/src/reax_types.h
@@ -56,6 +56,7 @@
 #define ZERO                    (0.000000000000000e+00)
 #define REAX_MAX_STR            (1024)
 #define REAX_MAX_NBRS           (6)
+#define REAX_MAX_NT_NBRS        (6)
 #define REAX_MAX_3BODY_PARAM    (5)
 #define REAX_MAX_4BODY_PARAM    (5)
 #define REAX_MAX_ATOM_TYPES     (25)