This is the 2021 release of FPLO which comes with a number of changes and new features:

- A bug in the creation of high symmetry points has been fixed.

This affects simple trigonal systems, which unfortunately where showing the high symmetry points of simple tetragonal. - A new k-mesh creation routine has optionally been added. It allows to pick isotropic subdivisions for centered lattices (of course still with symemtry restrictions, where they apply, e.g. in bct: Na=Nb but now Nc!=Na is possible)

The option is in the main fedit menu, hotkey M.

See FPLO21.00-61/DOC/MANUAL/doc.pdf: Section SCF-k-mesh - In both k-mesh creation routines a subdivision of 0 triggers automatice subdivision. See main fedit menu help screen for explanation.
- In Z2 mode the operator eigen functions are written.
- Wannier function module:
- There is an automode option in the wanniertools to create automatically all Wannier functions for the valence sector or for

all semi-core and valence orbitals. See DOC/pyfplo/pyfplo.pdf. - The xc-field can be obtained.
- The position operator (Berry connection of the basis) can be obtained.

…./FPLO21.00-61/DOC/pyfplo/Examples/slabify/Fe/SP/slabify/AHC/README - pyfplo:
- Berry curvature in pyfplo is now corrected for lack of symemtry. This is achieved by adding an approximation of the position operator matrix elements. The result for the periodic gauge has proper symmetry and does not change topological properties.

hamAtKPoint can be forced to return the relative gauge (gauga=’forcerelative’) if makedhk==True.

The pyfplo interface for Wannier centers (TI) has now an option to use the relative gauge with proper correction terms, which yields properly symmetric Wannier enter curves. The topological indices should not be affected. - make python3 in PYTHON will create a python3 package
- The pyfplo module FPLOInput has a cif-file import option with optional symmetry determination function called structureFromCIFFile. See DOC/pyfplo/pyfplo.pdf.
- The xc-field can be obtained.
- Mirror chern numbers
- symmetry operators of Wannier function Bloch sums and Hamiltonian
- the whole =.-file content can be scanned into a json file.

- Berry curvature in pyfplo is now corrected for lack of symemtry. This is achieved by adding an approximation of the position operator matrix elements. The result for the periodic gauge has proper symmetry and does not change topological properties.
- xfplo:
- The symmetry operations can be visualized in structure mode.
- The export button in the symmetry menu of xfplo has now a cif-export option.
- The high symmetry points in the Fermi-surface module are classified according to symmetry points, lines and optionally planes and general points are available.

Dresden, Dezember 2021.

Klaus.