Hi. Everyone.<br> I am performing some test works on graphene system with electric-enthalpy approach which was developed by Umari & Souza,<br>to examine its dielectric properties. <br> My calculation came to scf convergence problem when i applied E=
0.001 a.u.that is perpendicular to the graphene plane, the total-energy of this system oscillates up and down as shown below :<br>"<br> total energy = -22.10984675 Ry<br> total energy = -
31.05580980 Ry<br> total energy = -21.97194327 Ry<br> total energy = -22.49028278 Ry<br> total energy = -22.62216901 Ry<br> total energy = -23.00354121
Ry<br> total energy = -24.57862186 Ry<br> total energy = -21.98569845 Ry<br> total energy = -24.92584359 Ry<br> total energy = -24.96325979 Ry<br>
total energy = -22.09410112 Ry<br> total energy = -32.84912151 Ry<br> total energy = -22.00923042 Ry<br> total energy = -27.67266074 Ry<br> total energy = -
29.60728014 Ry<br> total energy = -21.49630504 Ry<br> total energy = -23.72936622 Ry<br> total energy = -23.50209359 Ry<br> total energy = -22.52577866
Ry<br><br>"<br><br>Would anyone please give me some suggestion or comments ,et al ? My running script is given below.<br><br><br><br>Best Wishes,<br><br>H.P<br><br><a href="http://graphene.scf.efield2.in">graphene.scf.efield2.in
</a><br><br>"<br> &control<br> calculation='scf'<br> restart_mode='restart',<br> prefix='graphene-SL',<br> gdir=3,<br> nppstr=1,<br> lelfield=.true.,<br> nberrycyc=6
<br> pseudo_dir='/home/haiping/espresso-3.2/pseudo',<br> outdir='/home/haiping/tmp'<br> /<br> &system<br> ibrav= 4, celldm(1)=4.648726267482302,<br> celldm(3)= 5,<br> nat= 2, ntyp= 1,<br>
ecutwfc = 30.0, nosym=.true.<br> /<br> &electrons<br> diagonalization='cg',<br> conv_thr = 1.0d-8,<br> mixing_beta = 0.01,<br> startingwfc='random',<br> efield=0.001,<br> /<br>ATOMIC_SPECIES
<br> C 12.0107 C.pz-rrkjus.UPF<br>ATOMIC_POSITIONS<br> C 0.0000 0.000000 0.0<br> C 0.3333 0.666667 0.0<br>K_POINTS<br> 16<br> 0.0 0.0 0.0 1<br> 0.0 0.25 0.0 1<br> 0.0 0.50 0.0 1<br> 0.0 0.75 0.0 1<br>
0.25 0.0 0.0 1<br> 0.25 0.25 0.0 1<br> 0.25 0.50 0.0 1<br> 0.25 0.75 0.0 1<br> 0.50 0.0 0.0 1<br> 0.50 0.25 0.0 1<br>0.50 0.50 0.0 1<br> 0.50 0.75 0.0 1<br> 0.75 0.0 0.0 1<br> 0.75 0.25 0.0
1<br> 0.75 0.50 0.0 1<br> 0.75 0.75 0.0 1<br>"<br><br><br> <br> <br><br clear="all"><br>-- <br>Hai-Ping Lan <br>Department of Electronics ,<br>Peking University , Bejing, 100871<br><a href="mailto:lanhaiping@gmail.com">
lanhaiping@gmail.com</a>, <a href="mailto:hplan@pku.edu.cn">hplan@pku.edu.cn</a>