diff --git a/src/atom.h b/src/atom.h
index bc49b11382..a87b66fed5 100644
--- a/src/atom.h
+++ b/src/atom.h
@@ -90,6 +90,7 @@ class Atom : protected Pointers {
   // customize by adding new flag
 
   int sphere_flag,ellipsoid_flag,line_flag,tri_flag,peri_flag,electron_flag;
+  int ecp_flag;
   int wavepacket_flag,sph_flag;
 
   int molecule_flag,q_flag,mu_flag;