<div dir="ltr"><div><span style="color:rgb(136,136,136);font-family:arial,sans-serif;font-size:13px">Dear Aline, if you are using FCC structure (ibrav=2), you must to use only "one" atom, at the position 0.00 0.00 0.00, and change "nat=1"</span></div>
<div><font color="#888888" face="arial, sans-serif">Please read about that in any solid state book.</font></div><div><font color="#888888" face="arial, sans-serif"><br></font></div><div><font color="#888888" face="arial, sans-serif">Best</font></div>
<div><font color="#888888" face="arial, sans-serif"><br></font></div><div><font color="#888888" face="arial, sans-serif">PhD. Arles V. Gil Rebaza</font></div><div><font color="#888888" face="arial, sans-serif">Instituto de Física de La Plata</font></div>
<div><font color="#888888" face="arial, sans-serif">La Plata - Argentine</font></div></div><div class="gmail_extra"><br><br><div class="gmail_quote">2014-05-05 18:19 GMT-03:00 Ari P Seitsonen <span dir="ltr"><<a href="mailto:Ari.P.Seitsonen@iki.fi" target="_blank">Ari.P.Seitsonen@iki.fi</a>></span>:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><br>
Dear Aline A Bidoul,<br>
<br>
You might want to check how many atoms are in the fcc unit cell if you indeed use the FCC as the basis (ibrav = 2).<br>
<br>
Greetings,<br>
<br>
apsi<br>
<br>
-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=<u></u>*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=<u></u>-=*=-=*=-=*=-=*=-<br>
Ari Paavo Seitsonen / <a href="mailto:Ari.P.Seitsonen@iki.fi" target="_blank">Ari.P.Seitsonen@iki.fi</a> / <a href="http://www.iki.fi/~apsi/" target="_blank">http://www.iki.fi/~apsi/</a><br>
Institut für Chemie der Universität Zürich, CH-8057 Zürich<br>
Tel: +41 44 63 54 497 / Mobile: +41 79 71 90 935<br>
<br>
<br>
On Mon, 5 May 2014, Aline Bidoul wrote:<br>
<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Hi everyone!I'm new in Quantum-Espresso and i having problems to minimize que lattice parameter of gold<div><div class="h5"><br>
The minimum energy is with 7.0A and in literature we find 4.07 A and in other programs i find 4.2<br>
I'm using this code to calculate the curve<br>
<br>
#!/bin/sh<br>
##############################<u></u>##############################<u></u>########<br>
#<br>
# define the following variables according to your needs<br>
#<br>
#espresso_dir=top_directory_<u></u>of_espresso_package<br>
outdir=/home'<br>
pseudo_dir=/home/pseudo'<br>
##############################<u></u>##############################<u></u>########<br>
<br>
rm -f au.scf.out au.etot_vs_alat<br>
touch au.etot_vs_alat<br>
<br>
for alat in 4.05 4.06 4.07 4.08 4.09 4.1 4.2 5.0 6.0 7.0 8.0 9.0 ; do<br>
<br>
# self-consistent calculation<br>
cat > <a href="http://au.scf.in" target="_blank">au.scf.in</a> << EOF<br>
&control<br>
calculation = 'scf'<br>
prefix='gold',<br>
pseudo_dir = pseudo_dir,<br>
outdir= outdir,<br>
/<br>
&system<br>
ibrav= 2, a=$alat , nat= 4, ntyp= 1,<br>
ecutwfc = 40.0, ecutrho = 480.0,<br>
occupations='smearing', smearing = 'mv', degauss = 0.002<br>
/<br>
&electrons<br>
mixing_mode = 'local-TF'<br>
mixing_beta = 0.7<br>
conv_thr = 1.0d-6<br>
/<br>
ATOMIC_SPECIES<br>
Au 196.96654 Au.bp-van_ak.UPF<br>
ATOMIC_POSITIONS (crystal)<br>
Au 0.00 0.00 0.00<br>
Au 0.5 0.5 0.0<br>
Au 0.5 0.0 0.5<br>
Au 0.0 0.5 0.5<br>
K_POINTS automatic<br>
8 8 8 1 1 1<br>
<br>
EOF<br>
<br>
pw.x < <a href="http://au.scf.in" target="_blank">au.scf.in</a> > au.scf.out<br>
<br>
grep -e 'lattice parameter' -e ! au.scf.out | \<br>
awk '/lattice/{a=$(NF-1)}/!/{print a, $(NF-1)}' >> au.etot_vs_alat<br>
<br>
done<br>
<br>
I find this in a tutorial of Professor Narasimhan. 7.0 A i think is large for gold, so i try to find for Silver and the alat was almost the same. I tested all the PP for gold that<br>
i find in the QE page, and has the same result with different energies values. If some one could help i will be grateful.<br>
<br>
<br>
--<br></div></div>
Aline A. BidoulEngenheira Física<br>
Mestranda em Engenharia Biomédica<br>
<br>
</blockquote>
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