Graduate Quantum Espresso Tutorial: h-Boron Phosphide Variable-Cell Relaxation

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The discussion focuses on using Quantum Espresso for simulating a hexagonal boron phosphide primary cell, specifically addressing issues with atom distances being too short and an incorrect Fermi level. The user has attempted various configurations without success and seeks assistance in verifying their input parameters for the variable-cell relaxation. Key parameters include a high energy cutoff and specific settings for electron dynamics and ion dynamics. The community is encouraged to review the provided input script to help troubleshoot the simulation issues. The user is eager for feedback and further progress in their Quantum Espresso project.
Alessandroocj
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Hello my dear fellows, how're you doing? I'm trying to learn how to use Quantum Espresso, and in order to do this, I'm trying to simulate a hexagonal boron phosphide primary cell. At the end of the simulation, the structure seems to be fine, but sometimes the distance of the atoms are too short, and the Fermi level seems to be wrong in all my attempts to solve the problem. I've already tried many different configurations. Could someone gently check my input to see if everything is OK? =)
Here is my input for the variable-cell relaxation

!===========================================================
!
! Quantum Espresso calculation - h-Boron Phosphide
! Variable-cell relaxation
!===========================================================
&CONTROL

calculation='vc-relax'
title='h-bp'
prefix='h-bp'
verbosity='high'
restart_mode='from_scratch'
!nstep=1000
!iprint=1
outdir='./results'
pseudo_dir='./'
!tstress=.true.
forc_conv_thr=1.0d-5
etot_conv_thr=1.0d-6

/

&SYSTEM

ibrav = 0, !lattice is specified below
nat = 2,
ntyp = 2,
ecutwfc = 100.0 ,
ecutrho = 700.0 ,
input_DFT = 'PBE' ,
!occupations = 'smearing',
!degauss = 1.0d-4 ,
!smearing ='marzari-vanderbilt' ,
lspinorb=.true.
noncolin=.true.

/

&ELECTRONS

electron_maxstep = 500,
conv_thr = 1.0d-10,
mixing_mode = 'plain',
mixing_beta = 0.7d0,
diagonalization = 'cg',

/

&IONS
ion_dynamics='bfgs'
upscale=20.0

/

&CELL

! press_conv_thr = 0.5D0
! press = 0.D0
! cell_dynamics = bfgs,
! cell_dofree = '2Dxy'
cell_factor = 3.0D0

/

ATOMIC_SPECIES

B 10.810 B.rel-pbe-n-kjpaw_psl.0.1.UPF
P 30.974 P.rel-pbe-n-kjpaw_psl.1.0.0.UPF

CELL_PARAMETERS (angstrom)

2.1300000 1.2300000 0.0000000
2.1300000 -1.2300000 0.0000000
0.0000000 0.0000000 6.0000000

ATOMIC_POSITIONS (angstrom)

B 0.000000000 0.000000000 3.000000000

P 1.300000000 0.000000000 3.000000000

K_POINTS automatic

12 12 1 0 0 0
 
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