Dear quantum espresso community,
  I am trying to calculate the critical temperature of superconductivity in 
boron doped diamond by quantum espresso-5.1. I provide the scf-calculation 
using 24x10x10 k-points for cell size 4.17x14.35x11.75Å.
For phonon dispersion calculation I use very coarse grid of q-points (3x2x2) 
because the unit cell have not any symmetry and the calculation will take a lot 
of time. I have got that lambda dependence strongly changes with increasing of 
degauss (see attached figure). Would you be so kind to explain me which 
parameters in input files affect on lambda and how improve my results?  And how 
can I distinguish the correct value of Tc and lambda from this dependencies?
Thank you in advance!
  Here are my input files
File for scf-calculation
  &control
calculation='scf'
restart_mode='from_scratch',
tstress = .true.
tprnfor = .true.
prefix='c',
pseudo_dir = '.',
outdir='.',
nstep = 200 
wf_collect=.true.,
/
&system
nosym=.false.,
ibrav= 0, 
celldm(1) = 0, 
nat= 18, 
ntyp= 2,
ecutwfc=32.0,
ecutrho=200.0,
occupations='smearing',
smearing='methfessel-paxton', 
degauss=0.05,
la2F = .true.,
CELL_PARAMETERS
0 14.3554 0
4.1796 2.4159 0.0057
0 0 11.7448
ATOMIC_SPECIES
C 12.0108 C.pz-vbc.UPF
B 10.8120 B.pz-vbc.UPF
ATOMIC_POSITIONS crystal
C 0 0 0
…
C 0.5 0.5 0.5
\
K_POINTS automatic 
24 10 10 0 0 0
  File for Electron-phonon coefficients for BC
&inputph
tr2_ph=1.0d-10,
prefix='c',
fildvscf='cdv',
amass(1)=12.0108,
amass(2)=10.8120,
outdir='./',
fildyn='c.dyn',
electron_phonon='interpolated',
trans=.true.,
ldisp=.true.,
nq1=3, nq2=2, nq3=2
alpha_mix(1)=0.7, 
/ --
Sergey Erohin
Student of Moscow Institute of Physics and Technology State University 
9 Institutskiy per., Dolgoprudny, Moscow Region, 141700, Russian Federation


-- 
Сергей Ерохин
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