diff --git a/gmso/core/atom_type.py b/gmso/core/atom_type.py
index a664bd45a..6405f69ac 100644
--- a/gmso/core/atom_type.py
+++ b/gmso/core/atom_type.py
@@ -129,10 +129,7 @@ def __hash__(self):
                     self.name,
                     unyt_to_hashable(self.mass),
                     unyt_to_hashable(self.charge),
-                    self.expression,
-                    tuple(self.independent_variables),
-                    tuple(self.parameters.keys()),
-                    tuple(unyt_to_hashable(val) for val in self.parameters.values())
+                    self.potential_expression
                 )
             )
         )
diff --git a/gmso/tests/test_atom_type.py b/gmso/tests/test_atom_type.py
index 4586876f9..021018689 100644
--- a/gmso/tests/test_atom_type.py
+++ b/gmso/tests/test_atom_type.py
@@ -1,3 +1,4 @@
+from copy import deepcopy
 import unyt as u
 import sympy
 import pytest
@@ -216,3 +217,7 @@ def test_with_1000_atom_types(self):
         assert len(top.atom_types) == 1
         assert top.n_sites == 1000
 
+    def test_atom_type_copy(self, typed_ethane):
+        for atom_type in typed_ethane.atom_types:
+            assert atom_type.copy(deep=True) == atom_type
+            assert deepcopy(atom_type) == atom_type