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Dear all,<br>
<br>
I want to calculate the energy of the O2 in its triplet ground
state. I have searched on the sites
(<a class="moz-txt-link-freetext" href="http://qe-forge.org/pipermail/pw_forum/2012-July/099147.html">http://qe-forge.org/pipermail/pw_forum/2012-July/099147.html</a>) and
do some tentative calculations.<br>
<br>
Firstly, I calculated the two O atoms in a enough large box. the
input file is:<br>
<br>
<small> &control<br>
calculation = 'relax'<br>
prefix = 'O2'<br>
pseudo_dir = '/'<br>
outdir = '/'<br>
/<br>
&system<br>
ibrav = 1, celldm(1) = 30.0<br>
nat = 2, ntyp = 1,<br>
ecutwfc = 35, ecutrho = 280<br>
occupations = 'smearing', degauss = 0.01<br>
nspin = 2, starting_magnetization(1) = 0.3<br>
/<br>
&electrons<br>
mixing_mode = 'plain'<br>
mixing_beta = 0.3<br>
conv_thr = 1.0d-8<br>
electron_maxstep = 200<br>
/<br>
&ions<br>
ion_dynamics = 'bfgs'<br>
/<br>
ATOMIC_SPECIES<br>
O 15.999 O.pbe-n-kjpaw_psl.1.0.0.UPF<br>
ATOMIC_POSITIONS {angstrom}<br>
O 5.000576334 5.029093041 5.029093041<br>
O 5.009423666 5.870906959 5.870906959<br>
K_POINTS {gamma}</small><br>
<br>
Secondly, I calculated the single O atom.<br>
<br>
Finally, I calculated the binding energy of O2 by "2 x single O atom
energy - O2 eneygy". But I am not sure it is correct or not. My
question is if the "binding energy" is close to the experimental
value ~ 5.7 eV, does it mean that the calculated energy of O2 is
accurate?<br>
<br>
Thanks in advance.<br>
<br>
Sincerely,<br>
<br>
S. Zhao<br>
--<br>
PhD candidate<br>
Graduate School of Life Science and Systems Engineering<br>
Kyushu Institute of Technology, Japan
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