Release Notes¶

0.6.2-11¶

Bug Fixes¶

Fixes the tutorial for the excited state solvers. In doing so, the EvaluationRule is properly exposed for importing and documenting accordingly.

Fixes the computation of ElectronicEnergy.coulomb() (and by extension ElectronicEnergy.fock()) when applied to a purely alpha-spin Hamiltonian but providing a mixed spin density.

0.6.2¶

Bug Fixes¶

Fixes the behavior of the FreezeCoreTransformer when a charge is present on the molecule.

Fixes the behavior of SpinOp.to_matrix() for operators acting on more than a single spin.

0.6.1¶

Bug Fixes¶

The ActiveSpaceTransformer would sometimes set the wrong number of active particles because of a flawed integer rounding. This has now been fixed.

Fixes a formatting issue when printing an ElectronicStructureResult which contains values in extracted_transformer_energies

The ElectronicStructureProblem.reference_energy is now properly propagated to the ElectronicStructureResult.hartree_fock_energy.

Fixes a regression in the performance of the map() method

Compatibility fix to support optional sparse install under Python 3.11.

Fixed the support of use_pauli_sum_op in the UCC and UVCC classes as well as their extensions. This requires version 0.24 or higher of the qiskit-terra package.

0.6.0¶

Prelude¶

Qiskit Nature 0.6 focuses on refactoring of the mappers module. To that extent, the QubitConverter class has been deprecated in favor of using the various subclasses of QubitMapper directly. As a short example, while you were doing something similar to this until now:

solver = GroundStateEigensolver(
    QubitConverter(ParityMapper(), two_qubit_reduction=True),
    VQE(...),
)
result = solver.solve(problem)

you now simply do the following instead:

solver = GroundStateEigensolver(
    ParityMapper(num_particles=problem.num_particles),
    VQE(...),
)
result = solver.solve(problem)

Check out the migration guide for the QubitConverter for more details. Besides this major refactoring, a few other changes have been done, so be sure to check out the migration guide from 0.5 to 0.6.