diff --git a/src/mdevaluate/coordinates.py b/src/mdevaluate/coordinates.py
index 3cd737f..5fc576a 100755
--- a/src/mdevaluate/coordinates.py
+++ b/src/mdevaluate/coordinates.py
@@ -514,7 +514,7 @@ def vectors(coordinates, atoms_a, atoms_b, normed=False):
         coords_b = coords_b.mean(axis=0)
     vec = pbc_diff(coords_a, coords_b, box=box)
     if normed:
-        vec / np.linalg.norm(vec, axis=-1).reshape(-1, 1)
+        vec /= np.linalg.norm(vec, axis=-1).reshape(-1, 1)
     vec.reference = coords_a
     return vec