<html><body><div style="font-family: arial, helvetica, sans-serif; font-size: 12pt; color: #000000"><div>dear all<br data-mce-bogus="1"></div><div>i want to relax atomic coordinates and lattic constants for graphene bilayer. but it dosen't converge.<br data-mce-bogus="1"></div><div>input file is:<br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div> &CONTROL<br> title = GRAPHENEBILAYER ,<br> calculation = 'vc-relax' ,<br> restart_mode = 'from_scratch' ,<br> wf_collect = .true. ,<br> outdir = './out' ,<br> wfcdir = './out' ,<br> pseudo_dir = './' ,<br> prefix = 'GBI' ,<br> verbosity = 'high' ,<br> etot_conv_thr = 1.0D-4 ,<br> forc_conv_thr = 1.0D-4 ,<br> tstress = .true. ,<br> tprnfor = .true. ,<br> /<br> &SYSTEM<br> ibrav = 4,<br> celldm(1) = 4.648726,<br> celldm(3) = 9.512195384,<br> nat = 4,<br> ntyp = 1,<br> ecutwfc = 50 ,<br> ecutrho = 500 ,<br> nosym = .false. ,<br> occupations = 'smearing' ,<br> degauss = 0.002 ,<br> smearing = 'gaussian' ,<br> /<br> &ELECTRONS<br> electron_maxstep = 200,<br> conv_thr = 1.0D-6 ,<br> mixing_beta = 0.3 ,<br> diagonalization = 'david' ,<br> /<br> &IONS<br> ion_dynamics = 'bfgs' ,<br> /<br> &CELL<br> cell_dynamics = 'bfgs' ,<br> cell_factor = 2.D0 ,<br> cell_dofree = '2Dxy' ,<br> /<br>ATOMIC_SPECIES<br> C 12.00000 C.blyp-mt.UPF <br>ATOMIC_POSITIONS crystal <br> C 0.333333330 0.666666660 0.572649573 <br> C 1.000000000 0.000000000 0.572649753 <br> C 0.666666660 0.333333330 0.427350427 <br> C 1.000000000 0.000000000 0.427350427 <br>K_POINTS automatic <br> 16 16 1 0 0 0 <br><br data-mce-bogus="1"></div><div><br data-mce-bogus="1"></div><div>best, <br data-mce-bogus="1"></div><div>sabike<br data-mce-bogus="1"></div></div></body></html>