Dear Chiara Thank you very much for the update! I was not aware yet of such new implementations and I was erroneously quoting from the 6.0 manual... Best Giuseppe
Quoting [email protected]: > Dear Dr. Kawamura thanks a lot for the patch. > > > Dear Giuseppe, > > after discussion of our collaborators with Paolo Giannozzi and > Stefano De Gironcoli, > > we learned that it is possible in QE v 6.1 to use tetrahedra for > relax and vc-relax calculations for insulators/semiconductors, > > especially using the the optimized tetrahedron method > (occupations='tetrahedra_opt'), as reported in the > > pw.x manual for version 6.1: > > Available options are: > > > 'smearing' : > > gaussian smearing for metals; > see variables > smearing<http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_PW.html#smearing> > and > degauss<http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_PW.html#degauss> > > > 'tetrahedra' : > > Tetrahedron method, Bloechl's version: > P.E. Bloechl, PRB 49, 16223 > (1994)<https://journals.aps.org/prb/abstract/10.1103/PhysRevB.49.16223> > Requires uniform grid of k-points, to be > automatically generated (see card > K_POINTS<http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_PW.html#K_POINTS>). > Well suited for calculation of DOS, > less so (because not variational) for > force/optimization/dynamics calculations. > > > 'tetrahedra_lin' : > > Original linear tetrahedron method. > To be used only as a reference; > the optimized tetrahedron method is more efficient. > > > 'tetrahedra_opt' : > > Optimized tetrahedron method: > see M. Kawamura, PRB 89, 094515 > (2014)<https://journals.aps.org/prb/abstract/10.1103/PhysRevB.89.094515>. > Can be used for phonon calculations as well. > > > 'fixed' : > > for insulators with a gap > > > 'from_input' : > > The occupation are read from input file, > card > OCCUPATIONS<http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_PW.html#OCCUPATIONS>. > Option valid only for > a > single k-point, requires > nbnd<http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_PW.html#nbnd> > to be > set > in input. Occupations should be consistent > with the value of > tot_charge<http://www.quantum-espresso.org/wp-content/uploads/Doc/INPUT_PW.html#tot_charge>. > > > > Best, > > Chiara > > > > > ________________________________ > De : [email protected] <[email protected]> de la > part de Giuseppe Mattioli <[email protected]> > Envoyé : mercredi 18 octobre 2017 10:48:15 > À : [email protected] > Objet : Re: [Pw_forum] tetrahedra and vc-relax > > > Dear Chiara > You should not use occupations='tetrahedra' for relax or vc-relax > calculations! The reason is clearly stated in the pw.x manual. Use > smearing instead > > > Variable: occupations > > Type: CHARACTER > Description: > Available options are: > > 'smearing' : > gaussian smearing for metals; > see variables "smearing" and "degauss" > > 'tetrahedra' : > especially suited for calculation of DOS > (see P.E. Bloechl, PRB 49, 16223 (1994)). > Requires uniform grid of k-points, > automatically generated (see below). > Not suitable (because not variational) for > force/optimization/dynamics calculations. > > 'fixed' : > for insulators with a gap > > 'from_input' : > The occupation are read from input file, > card "OCCUPATIONS". Option valid only for a > single k-point, requires "nbnd" to be set > in input. Occupations should be consistent > with the value of "tot_charge". > > > HTH > Giuseppe > > Quoting [email protected]: > >> Dear all, >> >> I'm trying to perform a "vc-relax" calculation using the tetrahedron >> method with QE v 6.1. >> >> The calculation stops after having printed the final geometry, >> during the final scf step. >> >> It does not write any error and the scheduler only reports a >> segmentation fault. >> >> I have tried with both tetrahedra and tetrahedra_opt, but I have the >> same issue. >> >> The problem is not there if I do a "relax" calculation. >> >> Please find attached, the input and output of an example. >> >> Thanks in advance! >> >> Regards, >> >> Chiara Ricca >> >> --- >> >> Postdoctoral fellow >> >> University of Bern > > > > GIUSEPPE MATTIOLI > CNR - ISTITUTO DI STRUTTURA DELLA MATERIA > Via Salaria Km 29,300 - C.P. 10 > I-00015 - Monterotondo Scalo (RM) > Mob (*preferred*) +39 373 7305625 > Tel + 39 06 90672342 - Fax +39 06 90672316 > E-mail: <[email protected]> > > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum GIUSEPPE MATTIOLI CNR - ISTITUTO DI STRUTTURA DELLA MATERIA Via Salaria Km 29,300 - C.P. 10 I-00015 - Monterotondo Scalo (RM) Mob (*preferred*) +39 373 7305625 Tel + 39 06 90672342 - Fax +39 06 90672316 E-mail: <[email protected]> _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
