Dear Osmair V Oliveira,
Some quick comments/first reaction:
- Are you sure that there is only one atom in the cell? If it is the hcp
structure, there should be two, if I am not wrong
- Did you check the convergence of the results with respect to the
cut-off energy? This pp seems to contain the semi-core s and p states in
the valence, so I would guess something like 150+ Ry might be needed
- (I am not using the "cold" smearing, but maybe it is ok)
- 10^-15 as the convergence threshould, nice if you indeed can converge
the electronic structure so tightly, but seems to be somewhat exaggerated
to me
- The coordinates for the lonely atom seem to be in relative units but
you have specified 'Angstrom'; more digits might be needed for the
symmetry routines anyway ("Ti 1/3 2/3 1/4" would also be allowed, well
then at least the elder versions of 'XCrysDen' were not able to read the
line though)
- No comments about the input for the phonon code (first please check the
ones in the ground state calculation)
- I would recommend to use an 'outdir' different than the current
directory, to keep the directories cleaner
- Please next time use a more appropriate title for your email (and a
more complete affiliation if possible)
Greetings from Paris,
apsi
-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-
Ari Paavo Seitsonen / Ari.P.Seitsonen at iki.fi / http://www.iki.fi/~apsi/
Ecole Normale Sup?rieure (ENS), D?partement de Chimie, Paris
Mobile (F) : +33 789 37 24 25 (CH) : +41 79 71 90 935
On Wed, 17 Sep 2014, Osmair Vital Osmair wrote:
> Dear users,I am trying to calculate critical temperature for Titanium. I used
> the following
> files:
> Ti.scf.in
> ?&control
> ?? ?calculation='scf'
> ?? ?restart_mode='from_scratch',
> ?? ?prefix='Ti',
> ?? ?pseudo_dir = './',
> ?? ?outdir='./'
> ?/
> ?&system
> ?? ?ibrav = ?4,
> ?? ?celldm(1) = 5.576203,
> ?? ?celldm(3) = 1.587874,
> ?? ?nat = 1,
> ?? ?ntyp = 1,
> ?? ?occupations = 'smearing',
> ?? ?degauss = 0.03,
> ?? ?smearing = 'cold',
> ?? ?ecutwfc = 60.0,
> ?? ?la2F = .true.,
> ?/
> ?&electrons
> ?? ? mixing_beta = 0.7,
> ?? ? conv_thr = ?1.0d-15,
> ?? ? diagonalization = 'cg',
> /
> ATOMIC_SPECIES
> ?Ti ?47.88 Ti.pbe-sp-hgh.UPF
> ATOMIC_POSITIONS ANGSTROM
> ?Ti 0.33333 0.66667 0.25000
> K_POINTS {automatic}
> 8 8 8 0 0 0
>
> Question 1) The calculation is finished without error, but in the output file
> has the message ?"No symmetry found
> ?? ? ? ? ?(note: 23 additional sym.ops. were found but ignored
> ?? ? ? ? ? their fractional translations are incommensurate with FFT grid)".
> This is very interesting because I tested various inputs with different
> elements with hexagonal structure (Zr, Tc, Re...) the same?message?appear.
> So, is there any
> problem or bug with the ibrav = 4 (hexagonal)?
> In addiction, in the ph.x calculation using the input below, I found negative
> frequencies, these frequencies can be attributed to this message?
>
> Question 2)
> After the scf calculation, I performed ph.x using the file:
> ?&inputph
> ??tr2_ph=1.0d-16,
> ??prefix='Ti',
> ??fildvscf='aldv',
> ??amass(1)=47.88,
> ??outdir='./',
> ??fildyn='Ti.dyn',
> ??electron_phonon='interpolated',
> ??trans=.true.,
> ??ldisp=.true.
> ??nq1=4, nq2=4, nq3=4
> ?/
> In this calculation, the file Ti.dy0 has 36 points and it was generate
> 36?elph.* files. However, the kpoints.x generate 50 k-points:
> bravais lattice ?>> 4
> ?? ? filout [mesh_k] ?>>?
> ?? ? enter celldm(3) ?>> 1.587874?
> ?? ? mesh: n1 n2 n3 ? >> 8 8 8
> ?? ? mesh: k1 k2 k3 (0 no shift, 1 shifted) ?>> 0 0 0
> ?? ? write all k? [f] >>?
> ?? ? # of k-points ? == ? ?50 ?of ? 512
>
> If I use?mesh: n1 n2 n3 ? >> 4 4 4, I have 12 k-points
> So, I expected that the number o k-points generated by the kpoints.x is the
> same of the obtained by the ph.x. Is this corrected and how can I improve
> this?
>
> Thanks in advance.
> Osmair V. Oliveira
> Brazil
>
>
>
