[Pw_forum] convergence is not achieved, please help!!!

[Ganjar Kurniawan]

Dear QE user...
I`m trying to optimize geometry of Li2FeSiO4 structure using 'relax', but the result said that the " convergence NOT achieved after 100 iterations: stopping ". I have used the atomic position from the literature.

here it is the input that i use

&CONTROL
 calculation = 'relax', 
 restart_mode = 'from_scratch',
 nstep = 50
 outdir = '/home/ganjar/Li2FeSiO4/pmn21/normal/relax'
 pseudo_dir = '/share/apps/espresso-5.0.2/pseudo',
 prefix='files_lar'
 tprnfor = .true. 
 tstress = .true.
 etot_conv_thr = 1.0D-4, forc_conv_thr = 1.0D-2
/
&SYSTEM
ibrav=0, a = 6.3219, b = 5.3935, c = 4.9939, cosAB = 0, cosAC = 0, cosBC = 0, nat = 16, ntyp = 4, ecutwfc = 30, ecutrho = 240,
 occupations = 'smearing', smearing='marzari-vanderbilt', degauss= 0.015, nspin=1 
/
&ELECTRONS

 conv_thr = 1.0D-8
 diagonalization = 'david',  mixing_beta = 0.7, startingpot = 'atomic', startingwfc = 'random', tqr = .true.
/
&IONS
 ion_dynamics = 'bfgs'
/
ATOMIC_SPECIES
 Li  6.9410  Li.pbe-mt_fhi.UPF
 Fe  55.847  Fe.pbe-mt_fhi.UPF 
 Si  28.085  Si.pbe-mt_fhi.UPF 
 O   15.999  O.pbe-mt_fhi.UPF
CELL_PARAMETERS alat 
      
 1.000   0.000   0.000
 0.000   1.000   0.000
 0.000   0.000   1.000

ATOMIC_POSITIONS alat

Li  0.2498  0.3307  0.8023
Li  0.2501  0.6693  0.3023
Li  0.7498  0.6693  0.3023
Li  0.7501  0.3307  0.8023
Fe  0.5000  0.8261  0.7960
Fe  0.0000  0.1738  0.2960
Si  0.0000  0.8297  0.8112
Si  0.5000  0.1702  0.3112
O   0.2145  0.6849  0.7013
O   0.2854  0.3150  0.2013
O   0.7145  0.3150  0.2013
O   0.7854  0.6849  0.7013
O   0.0000  0.1231  0.7118
O   0.5000  0.8768  0.2118
O   0.5000  0.1794  0.6417
O   0.0000  0.8205  0.1417

K_POINTS automatic
2 4 4 0 0 0


what wrong with my input??? 

anybody can correct it??

Best regard

Ganjar Kurniawan
Bandung Institute of Technology, Indonesia
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