diff --git a/src/MANYBODY/pair_atm.cpp b/src/MANYBODY/pair_atm.cpp
index e960398ab3..c23aa6560d 100644
--- a/src/MANYBODY/pair_atm.cpp
+++ b/src/MANYBODY/pair_atm.cpp
@@ -15,10 +15,10 @@
    Contributing author: Sergey Lishchuk
 ------------------------------------------------------------------------- */
 
+
+#include <cmath>
+
 #include "pair_atm.h"
-
-#include <math.h>
-
 #include "atom.h"
 #include "citeme.h"
 #include "comm.h"