diff --git a/unittest/force-styles/tests/improper-distharm.yaml b/unittest/force-styles/tests/improper-distharm.yaml
index 5a3f4e08a5..1ae48c8488 100644
--- a/unittest/force-styles/tests/improper-distharm.yaml
+++ b/unittest/force-styles/tests/improper-distharm.yaml
@@ -15,7 +15,7 @@ improper_coeff: ! |
   2  45.0 6.2
 extract: ! |
   k 1
-  chi 1
+  d0 1
 natoms: 29
 init_energy: 3973.601605432119
 init_stress: ! |2-