Dear Dr. Giuseppe
You suggestion worked for me.
"occupations='smearing', smearing='gaussian', degauss=0.01,"
The structure even converged when I excluded the vdw_corr tag.
Thank you very much
Bhamu
On Tue, Jan 5, 2021 at 11:48 PM Giuseppe Mattioli <
giuseppe.matti...@ism.cnr.it> wrote:
>
> Dear K C Bhamu
> When you simulate molecules having a large amount of rotational
> degrees of freedom, I recommend to use first a tight-binding or
> empirical tool to explore configurations, to avoid high-energy
> structures. The following one is excellent, very easy to use and very
> fast to run.
>
> https://xtb-docs.readthedocs.io/en/latest/contents.html
>
> This said, your starting configuration was trapped in an unfortunate
> structure where two sp2 C atoms (numbers 33 and 35) were twisted
> instead of being planar. You probably removed two H atoms from sp3
> atoms without relaxing them. The following structure, simply optimized
> with a force-field, should not give problems (but I have not run the
> calculation...).
>
> 45
> Energy: 52.7144978
> H 8.48608 10.45663 13.88529
> C 10.12285 10.35161 10.80715
> H 9.750819.36965 10.43974
> C 11.49997 10.08512 11.39597
> H 12.307569.85722 10.70499
> C 11.75878 10.11652 12.72470
> C 10.64679 10.32692 13.74405
> H 10.743179.58583 14.56637
> H 10.73789 11.33550 14.19281
> C 9.24848 10.13193 13.14479
> H 9.072919.05796 12.91129
> C 9.14194 10.92818 11.85742
> H 8.10293 10.88215 11.46867
> H 9.38712 11.98966 12.08748
> C 8.94637 11.522018.84268
> C 10.25893 11.302879.59702
> H 9.13189 12.174917.96386
> H 8.19218 12.022979.48301
> H 8.54193 10.551558.48460
> H 10.65844 12.286369.92936
> H 10.98302 10.862138.87653
> C 13.174409.88279 13.22285
> H 13.118889.04537 13.95078
> H 13.837079.54798 12.39520
> C 15.69736 11.92481 15.44478
> H 16.74498 11.70891 15.74860
> H 15.07047 11.97162 16.36387
> C 15.58617 13.25420 14.70482
> H 16.14427 13.14997 13.74597
> C 14.09237 13.52300 14.41126
> H 14.03472 14.35009 13.67327
> H 13.54419 13.83190 15.32752
> C 13.36446 12.32498 13.84523
> C 13.87547 11.06693 13.87464
> C 15.21374 10.78810 14.53332
> H 15.142949.87981 15.16991
> H 15.94984 10.58575 13.72543
> C 16.23591 15.73576 14.79615
> C 16.23058 14.39236 15.52642
> H 16.75074 16.49369 15.42343
> H 15.20340 16.09456 14.60831
> H 16.77780 15.64679 13.83071
> H 15.70219 14.50766 16.49821
> H 17.28870 14.12285 15.73764
> H 12.40535 12.52093 13.38556
>
> Finally,
>
> > occupations='smearing',
> > smearing='mv',
> > degauss=0.005d0,
>
> This is just a fine way for me to calculate a bunch of unoccupied
> molecular orbitals, but there is no need to use 'mv', which is for
> metals and less stable than 'gaussian', suitable for an "insulator"
> such as your molecule. I would use instead
>
> occupations='smearing', smearing='gaussian', degauss=0.01,
>
> HTH
> Giuseppe
>
>
> Quoting "Dr. K. C. Bhamu" :
>
> > Dear QE Users
> > I wish you all a very happy new year 2021!
> >
> > I am running a molecule with QE_6.6 but facing a convergence problem.
> > I tried with and without 'local-TF' and both the options are not working.
> >
> > Could someone please have a look and suggest to me any solution?
> >
> >
> >
> > calculation = 'relax'
> > restart_mode = 'from_scratch'
> > outdir = './tmp'
> > pseudo_dir = '/home/kcbhamu/PPs'
> > prefix = 'pwscf'
> > ! disk_io = 'none'
> >verbosity = 'default'
> >etot_conv_thr = 0.0001
> >forc_conv_thr = 0.001
> >nstep = 400
> > tstress = .true.
> > tprnfor = .true.
> > /
> >
> >
> > ibrav=1,
> > celldm(1)=47.2431531141d0,
> > nat=45,
> > ntyp=2,
> > ecutwfc=65,
> > ecutrho=650,
> > occupations='smearing',
> > smearing='mv',
> > degauss=0.005d0,
> > vdw_corr = 'DFT-D3'
> > assume_isolated='mt'
> > /
> >
> >
> > electron_maxstep=999
> > conv_thr=1d-06,
> >
