[Pw_forum] Negative rho is large

[mayank gupta]

Dear All QE users


I am doing caclulation for ZrO2 monoclinic phase. In scf calculation I
took ecutwfc=75 Ry and ecut_rho=750. I am getting message  negative
rho up down 0.261e0.00 0.00 in output. i have used ultrasoft pseudo
potential. how to improve my result.
Here I paste my input scf file.


 &control

    calculation='scf'
    restart_mode='from_scratch',
    tstress = .true.
    tprnfor = .true.
    prefix='zro',
    pseudo_dir = '/home/mayank/pseudo/',
    outdir='/home/mayank/tmp2/'
 /
 &system
ibrav=    12 ,celldm(1)=10.0928877,celldm(2)=0.967796293,celldm(3)=0.979591837,
celldm(4)=-0.16074,celldm(5)=0.0,celldm(6)=0.0,  nat=    12 ,
ntyp=2,
ecutwfc=  75.00000000
ecutrho=750


/
 &electrons
conv_thr=1.0D-8
mixing_beta=0.3
diagonalization='david'
 /
&ions
/
ATOMIC_SPECIES
 Zr  91.22   Zr.pw91-nsp-van.UPF
 O   15.99   O.pw91-van_ak.UPF
ATOMIC_POSITIONS {crystal}
Zr       0.209735100   0.276043346   0.042234007
Zr       0.290264900   0.723956654   0.542234007
Zr       0.790264900   0.723956654   0.957765993
Zr       0.709735100   0.276043346   0.457765993
O        0.344714661   0.068493659   0.332481802
O        0.155285339   0.931506341   0.832481802
O        0.655285339   0.931506341   0.667518198
O        0.844714661   0.068493659   0.167518198
O        0.478408144   0.449572291   0.757453977
O        0.021591856   0.550427709   0.257453977
O        0.521591856   0.550427709   0.242546023
O        0.978408144   0.449572291   0.742546023



K_POINTS automatic
 4  4  4  1  1  1


Thanks

-- 
Mayank kumar gupta
Contact No- 9869834437
                  8097400037
                 8080458227