DFTB+, a software package for efficient approximate density functional theory based atomistic simulations

Added

• MPI-parallelization of Waveplot

• Generalization of mixers to also handle complex density matrices

• General range-separated, long-range corrected CAM hybrid functionals for ground-state periodic systems (MPI-parallel Fock-type exchange and energy gradient construction by neighbour-list and matrix-multiplication based algorithms)

• Generalization of non-periodic, ground-state LC-DFTB Hamiltonian to general range-separated, long-range corrected CAM hybrid functionals (MPI-parallelization of matrix-multiplication based Fock-type exchange construction, MPI-parallel matrix-multiplication based energy gradient evaluation, restart of matrix-multiplication based hybrid-DFTB calculations)

• Hybrid functionals for (molecular) non-collinear spin groundstate

• Electronic constraints on arbitrary regions, targeting the electronic ground state by determining a self-consistent constraint potential (restricted to Mulliken populations at the moment)

• Density Matrix construction on GPU using MAGMA-BLAS routines

• More control over output of data and band structures during MD calculations. By default, requesting printing of atomic charges, energies or forces in the input leads them to also be included in the md.out file.

• Printing of atom-resolved dispersion energies in detailed.out

• MAGMA GPU accelerated solver for the modes code

• Explicit keyword for gaussian electron temperature smearing (MP order 0)

• Linear response derivatives for atom positions (DFTB1/DFTB2 only) for cluster boundary conditions in low symmetry (non-degenerate) systems (and currently not MPI parallel)

• Addition of developer documentation for code internals in doc/dftb+/code/

• Optional GPU acceleration for the modes code via the MAGMA library and support for the divide and conquer and relatively robust LAPACK solvers

• ASI interface for accessing H, S and density matrix

Changed

• Components of xtb energies are now resolved

• Use least squares solution instead of inversion for XLBOMD force corrections

• Raise error if a non-SCC calculation is using hybrid functionals

• Raise a warning if neither the input of parser version is set in the input

• Degeneracy tolerance for perturbation theory switched to absolute tolerance of differences between eigenvalues.

Fixed

• Incorrect superposition of atomic densities written by Waveplot

• SK-file parser extra-/spline-tag sequence dependent

• Incorrect excited gradients for spin-polarized long-range corrected linear-response TD-DFTB calculations.

• Temporarily remove free energy for Delta-DFTB calculations, as this is not formally derived in the general case.

• DeltaDFTB purified forces used correctly.

• COSMO solvent models had a bug leading to the energy showing a dependence on the ordering of the atoms in the system.

• The GBSA model had a bug, leading to differences for various GFN models from xTB results (also affects DFTB hamiltonians).

• Solvents where RadiiScaling was specified with a unit conversion were scaled by the square of the conversion. Affects calculations using constructs of the form: Radii = * [AA] = {} where * is Values, vanDerWaalsRadiiBondi vanDerWaalsRadiiCosmo or vanDerWaalsRadiiD3

• Corrected the order of Methfessel-Paxton filling. It was producing filling that was 1 order lower than the one requested in the input. This is probably safe in most applications, the lowest order beyond Gauss smearing (0th order) is default for several other codes and already has linear and quadratic independence of the free energy wrt temperature. Default for Methfessel-Paxton smearing is now set to 1 (matching the results from the old default value).

• Remove duplicate printing of internal energy in results.tag

• Correct testing for incompatible Poisson boundary overrides when only one side of the box is marked as periodic

• Geometry error for periodic structures with open boundary contacts

• Enable CI test cases and fix a parser bug

• Fix backward compatibility bug from release 22.2 which led to dftb_pin.hsd files containing obsolete keywords