address comments

PennyLaneAI · Sep 20, 2024 · eb0670b · eb0670b
1 parent bfa9e2f
commit eb0670b
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/pennylane/spin/spin_hamiltonian.py b/pennylane/spin/spin_hamiltonian.py
@@ -16,7 +16,7 @@
 """
 
 import pennylane as qml
-from pennylane import X, Y, Z, math
+from pennylane import I, X, Y, Z, math
 from pennylane.fermi import FermiWord
 
 from .lattice import Lattice, _generate_lattice
@@ -736,7 +736,7 @@ def spin_hamiltonian(lattice):
             "Custom edges need to be defined and should have an operator defined as a `str`"
         )
 
-    opmap = {"X": X, "Y": Y, "Z": Z}
+    opmap = {"I": I, "X": X, "Y": Y, "Z": Z}
     hamiltonian = 0.0 * qml.I(0)
     for edge in lattice.edges:
         v1, v2 = edge[0:2]