<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
Dear Cao,<br>
I am new to graphene calculation, and there is some questions about
your input files.<br>
First, why do you use rectangular cell, not a trigonal primary cell?<br>
Second, is it necessary to consider the magnetization of graphene?
Can you share some paper on this?<br>
Thanks very much.<br>
<br>
Pengju Ren<br>
<br>
Dalian Institute of Chemical Physics, CAS<br>
<br>
<br>
On 05/21/2012 08:13 PM, Cao TF wrote:
<blockquote cite="mid:20120521121354.16813.qmail@ms.hfcas.ac.cn"
type="cite">
<meta http-equiv="Context-Type" content="text/html; charset=utf-8">
<title></title>
<div>Dear QE users, <br>
I have calculated the density of states (DOS) of pure graphene.
The supercell used in my work is a rectangular cell containing
60 carbon atoms. But something has puzzled me greatly. There is
always a little energy gap (~0.2 eV) in the DOS, which contracts
with the fact that graphene is zero gap semiconductor. Although
I have change many parameters. This problem has not been solved.
Here I give the input file and I will be greatly appreciated if
you can give me some suggestions. <br>
For scf.in <br>
&CONTROL <br>
title = 'graphene layer' , <br>
calculation = 'scf' , <br>
restart_mode = 'from_scratch' , <br>
outdir = './tmp' , <br>
pseudo_dir = '~pseudo' , <br>
prefix = 'graphene' , <br>
/ <br>
&SYSTEM <br>
ibrav = 8 , <br>
a = 12.31 , b = 12.79312342 , c = 12.000 , <br>
nat = 60 , <br>
ntyp = 1 , <br>
occupations = 'smearing' , <br>
tot_charge = 0.0, <br>
degauss = 0.02 , <br>
smearing = 'mp' , <br>
nspin = 2 , <br>
starting_magnetization(1) = 0.5 , <br>
ecutwfc = 30.0 , <br>
ecutrho = 300.0 , <br>
/ <br>
&ELECTRONS <br>
conv_thr = 1.0d-8 , <br>
mixing_mode = 'local-TF' , <br>
mixing_beta = 0.7 , <br>
diagonalization = 'david' , <br>
/ <br>
ATOMIC_SPECIES <br>
C 12.0107 C.pbe-rrkjus.UPF <br>
ATOMIC_POSITIONS crystal <br>
C 0.0000000 0.0000000 0.50000000 <br>
C 0.10000000 5.55555671E-02 0.50000000 <br>
C 0.10000000 0.16666667 0.50000000 <br>
C 0.0000000 0.22222224 0.50000000 <br>
C 0.0000000 0.33333334 0.50000000 <br>
C 0.10000000 0.38888890 0.50000000 <br>
C 0.10000000 0.50000000 0.50000000 <br>
C 0.0000000 0.55555558 0.50000000 <br>
C 0.0000000 0.66666669 0.50000000 <br>
C 0.10000000 0.72222227 0.50000000 <br>
C 0.10000000 0.83333337 0.50000000 <br>
C 0.0000000 0.88888896 0.50000000 <br>
C 0.20000000 0.0000000 0.50000000 <br>
C 0.30000001 5.55555671E-02 0.50000000 <br>
C 0.30000001 0.16666667 0.50000000 <br>
C 0.20000000 0.22222224 0.50000000 <br>
C 0.20000000 0.33333334 0.50000000 <br>
C 0.30000001 0.38888890 0.50000000 <br>
C 0.30000001 0.50000000 0.50000000 <br>
C 0.20000000 0.55555558 0.50000000 <br>
C 0.20000000 0.66666669 0.50000000 <br>
C 0.30000001 0.72222227 0.50000000 <br>
C 0.30000001 0.83333337 0.50000000 <br>
C 0.20000000 0.88888896 0.50000000 <br>
C 0.40000001 0.0000000 0.50000000 <br>
C 0.50000000 5.55555671E-02 0.50000000 <br>
C 0.50000000 0.16666667 0.50000000 <br>
C 0.40000001 0.22222224 0.50000000 <br>
C 0.40000001 0.33333334 0.50000000 <br>
C 0.50000000 0.38888890 0.50000000 <br>
C 0.50000000 0.50000000 0.50000000 <br>
C 0.40000001 0.55555558 0.50000000 <br>
C 0.40000001 0.66666669 0.50000000 <br>
C 0.50000000 0.72222227 0.50000000 <br>
C 0.50000000 0.83333337 0.50000000 <br>
C 0.40000001 0.88888896 0.50000000 <br>
C 0.60000002 0.0000000 0.50000000 <br>
C 0.70000005 5.55555671E-02 0.50000000 <br>
C 0.70000005 0.16666667 0.50000000 <br>
C 0.60000002 0.22222224 0.50000000 <br>
C 0.60000002 0.33333334 0.50000000 <br>
C 0.70000005 0.38888890 0.50000000 <br>
C 0.70000005 0.50000000 0.50000000 <br>
C 0.60000002 0.55555558 0.50000000 <br>
C 0.60000002 0.66666669 0.50000000 <br>
C 0.70000005 0.72222227 0.50000000 <br>
C 0.70000005 0.83333337 0.50000000 <br>
C 0.60000002 0.88888896 0.50000000 <br>
C 0.80000001 0.0000000 0.50000000 <br>
C 0.90000004 5.55555671E-02 0.50000000 <br>
C 0.90000004 0.16666667 0.50000000 <br>
C 0.80000001 0.22222224 0.50000000 <br>
C 0.80000001 0.33333334 0.50000000 <br>
C 0.90000004 0.38888890 0.50000000 <br>
C 0.90000004 0.50000000 0.50000000 <br>
C 0.80000001 0.55555558 0.50000000 <br>
C 0.80000001 0.66666669 0.50000000 <br>
C 0.90000004 0.72222227 0.50000000 <br>
C 0.90000004 0.83333337 0.50000000 <br>
C 0.80000001 0.88888896 0.50000000 <br>
K_POINTS automatic <br>
8 8 1 0 0 0 <br>
For nscf.in <br>
&CONTROL <br>
title = 'graphene layer' , <br>
calculation = 'nscf' , <br>
restart_mode = 'from_scratch' , <br>
outdir = './tmp' , <br>
pseudo_dir = '/lustre/ISSP2/tfcao/pseudo' , <br>
prefix = 'graphene' , <br>
/ <br>
&SYSTEM <br>
ibrav = 8 , <br>
a = 12.31 , b = 12.79312342 , c = 12.000 , <br>
nat = 60 , <br>
ntyp = 1 , <br>
occupations = 'tetrahedra' , <br>
tot_charge = 0.0, <br>
nspin = 2 , <br>
starting_magnetization(1) = 0.5 , <br>
ecutwfc = 30.0 , <br>
ecutrho = 300.0 , <br>
/ <br>
&ELECTRONS <br>
conv_thr = 1.0d-8 , <br>
mixing_mode = 'local-TF' , <br>
mixing_beta = 0.7 , <br>
diagonalization = 'david' , <br>
/ <br>
ATOMIC_SPECIES <br>
C 12.0107 C.pbe-rrkjus.UPF <br>
For dos.in <br>
&inputpp <br>
prefix = 'graphene' , <br>
outdir = './tmp' , <br>
Emin = -4.0 , <br>
Emax = 4.0 , <br>
DeltaE = 0.01 , <br>
fildos = graphene.dos , <br>
/ <br>
The accessory is the DOS I have got. <br>
I am sorry for such a long file. I hope that you can give some
suggestions. <br>
======================================================================
<br>
Tengfei Cao, Research Laboratory for Computational Materials
Sciences, <br>
Instutue of Solid State Physics,the Chinese Academy of Sciences,
<br>
<br>
======================================================================
<br>
<br>
<br>
<br>
<br>
<br>
<br>
93,2 底端 <br>
1,2 顶端 <br>
</div>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
<pre wrap="">_______________________________________________
Pw_forum mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Pw_forum@pwscf.org">Pw_forum@pwscf.org</a>
<a class="moz-txt-link-freetext" href="http://www.democritos.it/mailman/listinfo/pw_forum">http://www.democritos.it/mailman/listinfo/pw_forum</a>
</pre>
</blockquote>
</body>
</html>