Quantum Espresso v5.1
New in 5.1 version:
- "Cold restart" for Car-Parrinello dynamics
- Calling QE from external codes made easier: see new subdirectory COUPLE
- PW: Hybrid functionals for USPP and PAW (experimental)
- PW: partial support to the use of k-point labels in the Brillouin zone
- PW: Langevin dynamics with Smart Monte Carlo
- CP and PW: Tkatchenko-Scheffler vdW correction (experimental)
- GWW replaced by GWL (using Lanczos chains)
- turboTDDFT: pseudo_Hermitian Lanczos algorithm and Davidson-like diagonalization added
- PWCOND with DFT+U
- New functionals: gau-pbe, PW86 (unrevised), B86B, XDM (exchange-hole dipole moment) model of dispersions, vdW-DF3, vdW-DF4 (Klimes et al), rVV10, optB86b-vdW, rev-vdW-DF2
- PHonon: Calculation of phonon dispersions using the finite displacements supercell approach. See subdirectory FD/ in PHonon.
- dynmat.x can calculate phonon contribution to dielectric tensor
- turboTDDFT now supports hybrid functionals (only with norm-conserving pseudopotentials)
- "image" parallelization re-introduced in pw.x: see code "manypw.x"
Incompatible changes in 5.1 version:
- Initialization of MPI modified in order to simplify usage of QE routines from external codes. It is now possible to run an instance of QE into a mpi communicator passed by the external routine. Changes affect a few MPI initialization routines (e.g. mp_start) and some MPI related modules; the communicator must be explicitly specified when calling mp_* interfaces to low-level MPI libraries.
- Input variable "london" should be replaced by " vdw_corr='Grimme-D2' "
- Routine "electrons" doesn't deal any longer with non-scf cases; use routine "non_scf" instead. For hybrid functionals, the loops over the charge density and over the exchange potential have been separated.
- Restart mechanism of pw.x changed a lot. It works ONLY if you stop the code cleanly with the prefix.EXIT file, or by setting "max_seconds"; disk_io='high' no longer needed (use it ONLY if tight with memory) Restarting from hard crashes is no longer supported.
- Major restructuring of DFT+U and related modules in PW: related variables moved to module ldaU, "swfcatom" moved to module "basis"
- Definition of "nwordwfc" in PP/ follows the same logic as in PW/
- Calls to "find_equiv_sites" and "writemodes" changed (fixed dimension "nax" removed)
- Call to "open_buffer" changed: unit must be a valid fortran unit > 0; max number of records is no longer specified; a new flag explicitly specifies if writing to RAM buffer is required. Functionalities of Modules/buffers.f90 have been considerably modified and extended.
Fixed in 5.1 version:
- PWscf: spin-polarized HSE for PAW was incorrectly implemented
- PHonon: Gamma-specific code wasn't properly restarting in parallel
- PHonon: epsil + paw was not working with k-point parallelization.
- PHonon: problem with the symmetry analysis in D_6h. The problem appeared in special cases after the symmetry reshuffling made by the phonon code.
- PWscf: starting with uniform charge worked only for non-spin-polarized calculations. Not a big deal unless one used HGH or other pseudopotentials without atomic charge information
- PWscf: Forces with finite electric field (lelfield=.true.) and US PP were incorrect in parallel execution
- D3: bug when the crystal has symmetry but the small group of the q-point has no symmetry.
- Bogus "file not found" error in pp.x when extracting quantities not requiring wave functions if these were "collected" - v.5.0.2 only
- Some quantities calculated in real space (including the charge itself when tqr=.true.) were not always accurately computed in parallel execution if the number of planes wasn't the same for all processors
- Bogus symmetry error in NEB due to missing re-initialization of fractional translations