Fix docs warning
@@ -890,7 +890,7 @@ class AbsoluteAlchemicalFactory(object):
"""Replace reaction-field electrostatics with Custom*Force terms to ensure c_rf = 0.
.. warning:: Unstable API.
- This method is still experimental. It could be moved in some
+ This method is still experimental. It could be moved to some
other module or have its signature changed in the near future.
A deep copy of the system is made.
