<html>
<head>
<meta content="text/html; charset=windows-1252"
http-equiv="Content-Type">
</head>
<body text="#000000" bgcolor="#FFFFFF">
Dear Felix.<br>
<br>
Is "binding energy" the same as (negative) "atomization energy" in
this context? Should be quite possible with PAWs.<br>
<br>
Regards,<br>
Jess<br>
<br>
<div class="moz-cite-prefix">On 02/26/2016 02:31 PM, Felix
Brockherde wrote:<br>
</div>
<blockquote
cite="mid:CAGVk6wwDQT7R2rPNu=sErCZw7mf=hu=wqYz6EJJH7DraigCHHQ@mail.gmail.com"
type="cite">
<div dir="ltr">
<div>Dear all,</div>
<div><br>
</div>
We would like to calculate the binding energy for
non-equilibrium H2O geometries with PAW pseudo potentials.<br>
<br>
The initial thought was to calculate the single-atom energies.
However, for H the system becomes metallic. We used smearing but
the results seem too far from the experimental value for us to
use them (-0.91784682 Ry).<br>
<br>
Now, we would like to calculate the binding energy by separating
the H2O molecule as far as necessary. We would thus avoid
inaccuracies caused by smearing because it is not a metallic
system. However, when pulling H2O apart, the DFT calculations do
not converge.
<div><br>
</div>
<div>Can anybody help with either how to get the separated H2O
converged or a different approach to get the binding energy
with PAW pseudo potentials?</div>
<div><br>
</div>
<div>We used PWSCF v.5.1.1 and I attached an input file where QE
does not converge.</div>
<div><br>
</div>
<div>Best regards,</div>
<div>Felix Brockherde</div>
<div>TU Berlin</div>
<div><br>
</div>
<div>
<div> &CONTROL</div>
<div> calculation = 'scf',</div>
<div> wfcdir = 'tmp',</div>
<div> pseudo_dir = '/home/user/pseudo_potentials',</div>
<div> tprnfor = .true.,</div>
<div> prefix = 'prefix',</div>
<div> tstress = .false.,</div>
<div> outdir = './',</div>
<div> wf_collect = .true.,</div>
<div> /</div>
<div> &SYSTEM</div>
<div> nat = 3,</div>
<div> ntyp = 2,</div>
<div> ecutwfc = 90,</div>
<div> ecutrho = 360,</div>
<div> celldm(1) = 30,</div>
<div> ibrav = 1,</div>
<div> /</div>
<div> &ELECTRONS</div>
<div> /</div>
<div>ATOMIC_SPECIES</div>
<div> H 1.00794 H_pbe-kjpaw_psl.0.1.UPF</div>
<div> O 15.9994 O_pbe-kjpaw_psl.0.1.UPF</div>
<div>ATOMIC_POSITIONS alat</div>
<div> O 0.5 0.3 0.5</div>
<div> H 0.5 0.7 0.3</div>
<div> H 0.5 0.7 0.7</div>
<div>K_POINTS automatic</div>
<div> 1 1 1 0 0 0</div>
</div>
</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://pwscf.org/mailman/listinfo/pw_forum">http://pwscf.org/mailman/listinfo/pw_forum</a></pre>
</blockquote>
<br>
</body>
</html>