<html><body><div style="color:#000; background-color:#fff; font-family:arial, helvetica, sans-serif;font-size:12pt"><div></div><div style="font-family: arial, helvetica, sans-serif; font-size: 12pt;"><div style="font-family: times new roman, new york, times, serif; font-size: 12pt;"><div id="yiv783031630"><div><div style="color:#000;background-color:#fff;font-family:arial, helvetica, sans-serif;font-size:12pt;"><div>Dear QE PWscf users,</div><div>I calculated scf, nscf,bands,plotband , dos and spin polarization of Graphene as a spintronic material.</div><div>The band structure that I got is not desired as a semimetal(i.e. graphene) and the spin polarization is <br></div><div>not desired(high %). <br></div><div><br></div><div>I am appreciate for any suggestion and comments.<br></div><pre><i>"Please tell me where I was wrong or which detail I ignored."</i></pre><div>I used the following PWscf code:</div><div><br></div><div><br></div><div>1. SCF
code:<br></div><div><br> </div><br> &control<br> calculation = 'scf'<br> restart_mode='from_scratch'<br> prefix='graphene'<br> tstress=.true.<br> tprnfor=.true.<br> pseudo_dir = '/home/live/Desktop/pseudo/',<br> outdir =
'/home/live/Desktop/testgraphene/'<br> /<br> &system<br> ibrav=4<br> celldm(1)=4.7243<br> celldm(3)=3.92<br> nat=2<br> ntyp=1<br> nspin=2<br> starting_magnetization(1)=0.6<br> ecutwfc=15.0<br> ecutrho=350.0<br> occupations='smearing'<br> smearing='gaussian'<br> nbnd = 8<br> degauss=0.01<br> /<br> &electrons<br> diagonalization='david'<br> electron_maxstep = 100<br> mixing_mode='plain'<br> mixing_beta=0.1<br> conv_thr = 1.0e-8<br> /<br> ATOMIC_SPECIES<br> C 12.011 C.pz-rrkjus.UPF<br> <br> <br> ATOMIC_POSITIONS (angstrom)<br> C 0.000000000 0.000000000 0.000000000<br> C 1.232850116 0.706423116 0.000000000<br> K_POINTS {automatic}<br> 16 16 1 0 0 0<br><br><br>2. NSCF code:<br> &control<br> calculation = 'nscf'<br>
restart_mode='from_scratch'<br> prefix='graphene'<br> tstress=.true.<br> tprnfor=.true.<br> pseudo_dir = '/home/live/Desktop/pseudo/',<br> outdir = '/home/live/Desktop/testgraphene/'<br> /<br> &system<br> ibrav=4<br> celldm(1)=4.7243<br> celldm(3)=3.92<br> nat=2<br> ntyp=1<br> nspin=2<br> starting_magnetization(1)=0.6<br> ecutwfc=15.0<br> ecutrho=350.0<br> occupations='smearing'<br> smearing='gaussian'<br> nbnd = 8<br> degauss=0.01<br> /<br> &electrons<br> diagonalization='david'<br> electron_maxstep = 100<br> mixing_mode='plain'<br> mixing_beta=0.1<br> conv_thr = 1.0e-8<br> /<br> ATOMIC_SPECIES<br> C 12.011 C.pz-rrkjus.UPF<br> <br> <br> ATOMIC_POSITIONS (angstrom)<br> C 0.000000000 0.000000000 0.000000000<br> C 1.232850116 0.706423116
0.000000000<br> K_POINTS {automatic}<br> 16 16 1 0 0 0<br><br><br><br><br>3.pw.x band code:<br> &control<br> calculation = 'bands'<br> restart_mode='from_scratch'<br> prefix='graphene'<br> tstress=.true.<br> tprnfor=.true.<br> pseudo_dir = '/home/live/Desktop/pseudo/',<br> outdir = '/home/live/Desktop/testgraphene/'<br> /<br> &system<br> ibrav=4<br> celldm(1)=4.7243<br> celldm(3)=3.92<br> nat=2<br> ntyp=1<br> nspin=2<br> starting_magnetization(1)=0.6<br> ecutwfc=15.0<br> ecutrho=350.0<br> occupations='smearing'<br> smearing='gaussian'<br> nbnd = 8<br> degauss=0.01<br> /<br> &electrons<br> diagonalization='david'<br> electron_maxstep = 100<br> mixing_mode='plain'<br> mixing_beta=0.1<br> conv_thr = 1.0e-8<br> /<br> ATOMIC_SPECIES<br> C
12.011 C.pz-rrkjus.UPF<br> <br> <br> ATOMIC_POSITIONS (angstrom)<br> C 0.000000000 0.000000000 0.000000000<br> C 1.232850116 0.706423116 0.000000000<br> K_POINTS {automatic}<br> 16 16 1 0 0 0<br><br><br>4.band.x code:<br>&inputpp<br> prefix='graphene',<br> outdir='/home/live/Desktop/testgraphene/'<br> !filband='graphene.bands'<br> / <br><br><br><br>5.plotband.x code:<br>bands.out<br>-10.0 20.0<br>graphene.xmgr<br>graphene.ps<br>1.000<br>2.0 1.00<br>EOF <br><br><br>6. dos.x code:<br> &inputpp<br> prefix='graphene'<br> outdir=/home/live/Desktop/Graphenenbnd8/'<br> fildos='graphene.dos',<br> Emin=-25.0, Emax=20.0, DeltaE=0.1<br><br><br>Regards-<br>Rahen Badsha (Raihan)<br>A post graduate Thesis student<br>University of Rajshahi, Bangladesh<br><br><br><br></div></div></div><br><br> </div> </div> </div></body></html>