diff --git a/qiskit_nature/problems/second_quantization/lattice/lattices/lattice.py b/qiskit_nature/problems/second_quantization/lattice/lattices/lattice.py index a6020b088d..7a5342630c 100644 --- a/qiskit_nature/problems/second_quantization/lattice/lattices/lattice.py +++ b/qiskit_nature/problems/second_quantization/lattice/lattices/lattice.py @@ -11,6 +11,7 @@ # that they have been altered from the originals. """General Lattice.""" +from copy import deepcopy from dataclasses import asdict, dataclass from typing import Callable, List, Optional, Sequence, Tuple, Union @@ -148,7 +149,7 @@ def weighted_edge_list(self) -> WeightedEdgeList: def copy(self) -> "Lattice": """Return a copy of the lattice.""" - return self.__class__(self.graph) + return deepcopy(self) @classmethod def from_nodes_and_edges(