[Pw_forum] Will the variance of pseudopotential lead to quite different results in the terms of total energy ?

[ＷＡＮＧ ＹＵＡＮＱＩＮＧ]

Dear all,

  Hi!!!
  I want to reproduce the results of one article (J. Phys. Chem. C, 2015, 119 (9), pp 4827–4833) because the authors kindly provide the raw input. Since they use the pseudopotential I can not find in the official website, I just change them to the pseudopotential in the official website. However, I found the results are quite different, even in the sense of relative energy. So, I wonder how I should choose the correct or reasonable psudopotential. 

          total_energy(my results)           total_energy(JPCC)
case 1    -251.52904868 Ry(0.)            -500.88392739 Ry(0.)
case 2    -251.86326485 Ry(-0.33421617)   -501.15752582 Ry(-0.27359843)
case 3    -252.00820845 Ry(-0.47915977)   -501.26364613 Ry(-0.37971874)
case 4    -252.04128086 Ry(-0.51223218)   -501.27151855 Ry(-0.38759116)
case 5    -252.00878190 Ry(-0.47973322)   -501.22233815 Ry(-0.33841076)


******input file***************
&CONTROL
 calculation = 'vc-relax'
 pseudo_dir = '/espresso-5.1.2/pseudo/'
/
&SYSTEM
 ibrav = 0
 nat = 6
 ntyp = 2
 nbnd = 78
 starting_magnetization(1) = 0.6
 starting_magnetization(2) = 0
 ecutwfc = 40
 ecutrho = 500
 occupations = 'smearing'
 degauss = 0.01
 smearing = 'mp'
 nspin = 2
 Hubbard_U(1) = 0
 Hubbard_U(2) = 0
 Hubbard_alpha(1) = 0
 Hubbard_alpha(2) = 0
/
&ELECTRONS
/
&IONS
/
&CELL
 cell_dofree = 'shape'
/
K_POINTS {automatic}
 5 5 5 0 0 0
ATOMIC_SPECIES
 Ir0 192.22 Ir.pbe-n-rrkjus.UPF    #ir_pbe_v1.uspp.F.UPF in the article
 O1 15.9994 O.pbe-n-rrkjus_psl.0.1.UPF  #o_pbe_v1.01.uspp.F.UPF
ATOMIC_POSITIONS {crystal}
 Ir0 0.00000 0.00000 0.00000 0 0 0
 Ir0 0.50000 0.50000 0.50000 0 0 0
 O1 0.30500 0.30500 0.00000 1 1 0
 O1 -0.30500 -0.30500 0.00000 1 1 0
 O1 0.80500 0.19500 0.50000 1 1 0
 O1 0.19500 0.80500 0.50000 1 1 0
CELL_PARAMETERS {angstrom}
 4.25368570224 0.0 0.0
 0.0 4.25368570224 0.0
 0.0 0.0 2.74126411922
****************************************

Thank you very much!!!

Best regards,

Yuanqing Wang