Changelog

For detailed release notes with code examples and feature walkthroughs, see the Release Notes section.

Version 2.1.0

See What’s New in Version 2.1 for full details.

  • Geometry optimization as a first-class algorithm type (geometry_optimizer), with a geomeTRIC-backed implementation driven by the existing nuclear derivative calculators

  • Vendored Q# utilities load into a private qdk.Context instead of the global interpreter, so importing qdk_chemistry no longer changes the caller’s target profile

  • Qiskit extras supported on Python 3.14

Bug fixes:

  • Corrected the iterative phase estimation phase convention: for \(U = e^{-iHt}\) the energy is recovered as \(E = -\theta / t\), the feedback phase is negated, and QpeResult.bits_msb_first is now genuinely most-significant-bit first

  • QpeResult files written by v1 are now upgraded by python -m qdk_chemistry.migrate

Version 2.0.0

See What’s New in Version 2.0 for full details and migration guidance.

  • Symmetry-blocked storage unifying restricted and unrestricted orbital, integral, and index data

  • Consolidated wavefunction containers (StateVectorContainer, AmplitudeContainer)

  • Nuclear gradients and finite-difference Hessians

  • Stabilized SCF and ROHF geometric direct minimization

  • Block-encoding/LCU qubitization, Hadamard test, and Zassenhaus product formulas

  • Real-time dynamics for driven, time-dependent Hamiltonians

  • Fermion-to-qubit mapping carried as data (MajoranaMapping), including a Verstraete-Cirac encoding

  • Explicit Pauli term grouping and generalized expectation estimation

  • Composable standard and iterative phase-estimation circuit builders

  • QDK Quantum Resource Estimator integration for generated circuits (Circuit.estimate / get_qre_application)

  • Algorithm result caching and data-file migration tooling

  • Windows build support with CI

Breaking changes:

  • Wavefunction containers consolidated from five classes into two: SlaterDeterminantContainer, CasWavefunctionContainer, and SciWavefunctionContainer (structurally identical apart from a type tag) merge into StateVectorContainer, distinguished by a stored sector; MP2Container and CoupledClusterContainer merge into AmplitudeContainer, distinguished by an AmplitudeType tag. Wavefunction.get_container_type() now returns "state_vector" / "amplitude" (old names remain as deprecated aliases)

  • Serialization schema bumped from 0.1.0 to 0.2.0 for the Orbitals / ModelOrbitals, CanonicalFourCenterHamiltonianContainer / SparseHamiltonianContainer / CholeskyHamiltonianContainer, Wavefunction / StateVectorContainer, QpeResult, and UnitaryRepresentation data classes; AmplitudeContainer and the top-level Hamiltonian are unchanged. Upgrade supported files with python -m qdk_chemistry.migrate; v1 TimeEvolutionUnitary files must be regenerated because they do not store the scale required by v2

  • Expectation estimator no longer auto-groups terms

  • Qubit mapper takes a MajoranaMapping instead of an encoding string

  • Silent semantic change: the Wavefunction accessor get_active_two_rdm_spin_dependent() now returns blocks as (aaaa, aabb, bbbb) (was (aabb, aaaa, bbbb)), with the aabb block in alpha-alpha-beta-beta index order (was alpha-beta-alpha-beta), to match the two-electron integral block order in Hamiltonian; the Wavefunction constructor takes the same new order. Positional unpacking reads incorrect data until updated

  • Configuration string and bitset constructors replaced by explicit factories

  • Phase estimation now uses the "qdk_iterative" and "qdk_standard" variants; num_bits, unitary-builder, evolution-time, and controlled-mapper settings belong to the nested qpe_circuit_builder reference, and the executor is configured through circuit_executor. The v1 "qiskit_standard" variant is composed from "qdk_standard" with Qiskit builder and executor references

  • Renames (deprecated aliases retained): QubitHamiltonian to QubitOperator, EnergyEstimator to ExpectationEstimator, TimeEvolutionUnitary to UnitaryRepresentation, and TimeEvolutionUnitaryContainer to UnitaryContainer

  • v1 Orbitals dense accessors deprecated in favor of the symmetry-blocked accessors

  • C++ only: FCIDUMP writer, Cholesky container, and ModelOrbitals constructor changes

Version 1.1.0

See What’s New in Version 1.1 for full details.

  • Q#-native circuit architecture with lazy QIR compilation

  • Model Hamiltonians (Hückel, Hubbard, PPP, Ising, Heisenberg)

  • Arbitrary-order Trotter-Suzuki product formulas

  • Native ROHF with DIIS acceleration

  • Cholesky-based AO→MO integral transformation

  • OpenFermion qubit-mapping plugin

  • MACIS active-space expansion to 2048 orbitals

  • One-shot VVHV orbital localization

Version 1.0.2

  • Make qiskit-aer and qiskit-nature optional dependencies

  • Loosen matplotlib version requirement to >=3.10.0

  • Fixed installation instructions for Ubuntu compatibility

  • Improved iQPE demo notebook

Version 1.0.1

  • Added support for Python 3.10

  • Enhanced INSTALL.md with clearer installation steps

Version 1.0.0

  • Initial release of QDK/Chemistry