Changes:

• Tests for the QM/MM transition state optimizer
• In case the atom coordinates given to a GeometryOptimizer are identical to the coordinates
  of the underlying calculator and a Hessian is requested,
  it is checked if this result is already present in the calculator to avoid an unnecessary calculation.
• The Thermochemical Calculator can now be constructed with a PartialHessian.
• The property PartialGradients is now available. It is intended to signal different contributions
  to the total gradients, e.g., the QM gradient contribution and the MM gradient contribution in QM/MM.
• Added a class to store derivatives in a more flexible manner.
• The Harmonic oscillator, particle-in-a-box, static-rotor free energy for zero Kelvin is now set to the
  sum of the electronic energy and zero point vibrational energy.
• Fixed a bug which lead to a crash when extracting thermochemical information from the Orca output for a
  temperature of zero Kelvin.
• Relative paths for the point charge file in electrostatic embedding calculations with Orca may now be used.
• More basis sets supported by Turbomole calculator.
• Pickle support for ElementType.
• The DFT grid for calculations with Turbomole is now set to 'm4' if Hessians are requested and the grid was
  too coarse for reliable Hessians (1 - 3, m3).
• Added support for lists of lists of integers as generic values.
• Added support for None in the Python bindings of the extract method of the Settings class.
• Allow writing pdb trajectory files.
• Fixes a bug where the coordinates in XYZ trajectory files were no longer separated by white spaces.
• Fixed a bug where the coordinates in PDB files were wrong if the code was compiled with clang.
• Added support for QM/QM/MM embedding and QM/QM embedding with Serenity.

Changes:

• Enable calculation of 57-Fe Mössbauer parameters with Orca.
• Enable DLPNO-CCSD(T)-F12 calculations with Orca.
• Added a MRCC calculator (requires MRCC executables at the MRCC_BINARY_PATH path
  environment variable).
  • Supported methods: DFT, HF, MP2 [LNO-MP2], CC [LNO-CCSD, LNO-CCSD(T)]
• Added transition state optimizer for QM/MM
• Molecular trajectories in the PDB file format can now be read.
• Improve support for compilation on Windows (MSVC)
• Update address in license

Changes:

• Turbomole calculator can now calculate Hessians numerically.
• The DFT grid for the Turbomole calculator can now be varied.
• The cavity construction for implicit solvation with the Turbomole calculator can now be modified by setting the points and segments per atom.
• Update Calculator interface helpers to accommodate pure Python3 Calculators.
• Added distortion of structure along a set of vibrational mode(s) and harmonic inversion point calculation.
• Changed Python state definition of ValueCollection to avoid faulty state for empty ValueCollections.

Changes:

• A custom implicit solvent may be defined for the Turbomole input creator through
  its dielectric constant and probe radius.
• Turbomole calculator can now carry out Hartree-Fock calculations.
• Orca calculator can now carry out broken-symmetry DFT calculations.
• Improve comparisons of periodic data structures.
• Ease communication between forked processes for monitoring calculations.
• Various bugfixes and improvements
• Added data structures for interfacing with integral libraries.
• The BondDetectors can alternatively rely on Van der Waals (VdW) radii instead of covalent radii.
• The PeriodicSystem generates its bond orders now per default based on VdW radii between solid state atoms.
• Turbomole calculator can now calculate excited states.
• The PdbStreamHandler can read multiple models in a pdb file (encoded by the MODEL tag in the file).
• Add Python bindings for D3/D3BJ dispersion corrections.
• Add additional setting to external QC calculators that allows to enforce the set SCF convergence criterion.
• The pressure for free energy calculations may now be changed. Current default 1 atm.
• Add Spglib dependency.
• Increase pickle support of Python bindings.
• Optimization related setting names are gathered in a separate namespace and removed from the optimizers

Changes:

• Newton Trajectory: Added new extraction options and improved eta bonds in NT2
• Added more solvents for the Turbomole input creator
• Added the Pauling electronegativity scale. This is available through the ElementInfo.
• Added solvate function to place any mixture of solvents around solute.
• PeriodicSystem canonicalizes the given PeriodicBoundaries to ensure read/write stability
• Calculators:
  • For the Turbomole calculator, allow the SCF damping value to be specified exactly (instead of predefined
    settings "default", "low", "medium", and "high")
  • Add "PBEH-3C" and "B97-3C" as supported method families for the ORCA calculator
• Settings for placing solvent molecules are summarized in SolventPlacementSettings, all solvate functions
  take only this structure as input. This change is not backwards compatible.
• Code deduplication

Changes:

• Add second version of Newton Trajectory algorithm (NT2) for elementary step induction
• Add Gaussian process regression
• Improve BFGS: guarantees positive-definite approximate Hessian
• B-Splines: interpolation and compression of trajectories including energy
• Enable optimization of a geometry together with its unit cell - CP2K:
  • Add xTB support
  • Add stress tensor
• Enable point charge embedding for Turbomole
• Add linear sum assignment algorithm
• Add functionality to evaluate the spin contamination of a single determinant
• Add Python bindings for WavefunctionOutputGenerator and casting utilities from Calculator and CalculatorWithReference.
• Calculators: - Harmonize dispersion correction input
• Code deduplication

Changes:

• Improve GDIIS: numerical stability
• Improve BFGS: add automatic damping
• Improve EVF and Bofill: allows to select mode and follows mode independent of order
• Add periodic boundary conditions
• Add support for CP2K
• Improve Gaussian interface: allows to reuse SCF results as guesses in subsequent calculations and to retrieve molecular orbital coefficients
• Add support for Turbomole
• Improve MD: Fix a bug regarding the time step size, check gradient calculations for SCF convergence, add the option to use bias potentials and add a stochastic dynamics integrator
• Add Python bindings for CalculatorWithReference
• Add Log accessor to Python bindings of Calculator and CalculatorWithReference
• Add Python bindings for Davidson diagonalizer with possibility of having custom sigma vector evaluators/preconditioners
• Add functions to get all closest atoms within a certain distance and to build an atom pair-list
• Distinguish now between true internal, true Cartesian, and Cartesian with removed translation and rotation coordinate systems
• Add Python bindings for ThermochemistryCalculator to calculate thermodynamic properties from a Hessian in Python
• Add Python bindings for SettingsNames
• Add support for the SMD solvation model in ORCA
• Add the option to obtain gradients from a CalculatorWithReference in MD simulations
• Refactoring of GeometryUtilities into sub-namespaces
• Add data structures needed for downstream methods that are general to linear response methods
• Remove Logger option for downstream LcaoMethods as it can be accessed through the calculator interface
• Refactor Davidson diagonalizers:
  • Create IterativeDiagonalizer interface
  • Create KrylovDiagonalizer interface, inheriting from IterativeDiagonalizer
  • Create the 2 versions, NonOrthogonalDavidson and OrthogonalDavidson
  • Add Python bindings for OrthogonalDavidson and NonOrthogonalDavidson, tested in Python and added an example on how to extend the SigmaVectorEvaluator to customize the Davidson directly in Python

Changes:

• Update development-utils

Changes:

• Enable conan builds and PyPI releases
• Add Newton-Trajectory type optimizer
• Add statistics and machine learning tools (PCA, k-fold cross-validation, kernel ridge regression)
• Add chemical representations for machine-learned force fields
• Charge Model 5 corrections for Hirshfeld atomic partial charges
• Add various conceptual DFT quantities
• Enable access to the density matrix and GTOs in Python
• Improve Dimer transition state search algorithm
• Add implicit solvation option to ORCA and Gaussian interfaces
• Add python bindings sphinx documentation
• Separate Settings from its base ValueCollection in python bindings

Changes:

• Add support for internal coordinates
• Add interface to Gaussian
• Improve ORCA interface (and make compatible with ORCA 4.2.0)
• Add BFGS optimizer and G-DIIS convergence accelerator
• Improve Bofill transition state search algorithm
• Various bugfixes and improvements