diff --git a/src/vatom/COM.cpp b/src/vatom/COM.cpp
index ffbd280d95b4ed6a2681695b5377e00558fceccc..50c960a9f90b59ac0fc89fc78fe2b991a2dd092f 100644
--- a/src/vatom/COM.cpp
+++ b/src/vatom/COM.cpp
@@ -76,6 +76,7 @@ COM::COM(const ActionOptions&ao):
 {
   vector<AtomNumber> atoms;
   parseAtomList("ATOMS",atoms);
+  if(atoms.size()==0) error("at least one atom should be specified");
   checkRead();
   log.printf("  of atoms");
   for(unsigned i=0;i<atoms.size();++i) log.printf(" %d",atoms[i].serial());
diff --git a/src/vatom/Center.cpp b/src/vatom/Center.cpp
index 3a399f19392ccc4560a85f19d90136bd7cb5541c..6fd0558c84e39a431591225b4e4ad28e8e6e21f7 100644
--- a/src/vatom/Center.cpp
+++ b/src/vatom/Center.cpp
@@ -88,6 +88,7 @@ Center::Center(const ActionOptions&ao):
 {
   vector<AtomNumber> atoms;
   parseAtomList("ATOMS",atoms);
+  if(atoms.size()==0) error("at least one atom should be specified");
   parseVector("WEIGHTS",weights);
   parseFlag("MASS",weight_mass);
   checkRead();