[Pw_forum] Hybridfunctionals in QE 5.1

[Paolo Giannozzi]

The default G-space implementation of exact-exchange terms with
USPP is very inefficient. For the same cutoff, a hybrid functional
run is much slower with USPP than with NCPP. The real-space
implementation (tqr=.true.) should be much more efficient

Paolo

On Wed, 2014-10-22 at 10:43 +0200, Florian Lazarevic wrote:
> Dear all,
> 
> recently I have installed the latest version of QE (Quantum ESPRESSO 5.10).
> I tried to set a hybridfunctional calculation (pbe0). I have used a mixture of NC-PP and US-PP. At the beginning the calculation seems to run properly. However, after/during the first few EXX-steps the run seems to stuck. But it did not crash (no error messages). It just keeps on running without writing output anymore. You can find the input-file below.
> 
> Is this problem related to the PP-Mixing? Without using US-PP (Ta.pbe-nsp-van.upf ) I dont observe such issues.
> In adition each done EXX-steps take very long time compaired to the none mixing case (> 400000s).
> 
> Best regards
> Florian
> 
> PS: Unfortunatly one of my favorite features - restart from hard crashes - is no longer supported. Are there plans to change this feature back.
> 
> ##input-file##
> &control
> calculation = 'scf'
> restart_mode='from_scratch',
> tstress = .true.
> tprnfor = .true.
> pseudo_dir = './pseudo',
> outdir='./scratch'
> prefix='HfO2_R',
> /
> &system
> celldm(1) = 19.5260000
> ibrav= 0,
> nat= 96,
> ntyp= 3,
> nbnd=400,
> nosym=.TRUE.
> ecutwfc =40.0,
> occupations='smearing',
> smearing='gaussian',
> degauss=0.01
> nspin=2, tot_magnetization=1,
> input_dft='pbe0', nqx1 = 1, nqx1 = 1, nqx3 = 1,
> exxdiv_treatment='gygi-baldereschi'
> ecutvcut=0.7
> x_gamma_extrapolation = .TRUE.
> /
> &electrons
> diagonalization='david'
> mixing_mode = 'plain'
> mixing_beta = 0.7
> conv_thr = 5.0d-6
> /
> ATOMIC_SPECIES
> Hf 178.49 hf_semi_NC_ebn_3.upf
> O 15.999 o_pbe.upf
> Ta 180.95 Ta.pbe-nsp-van.upf
> 
> CELL_PARAMETERS
> ...
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum