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Dear QE users,<br>
<br>
I am currently in the process of learning how to model hydrogen adsorption on a graphene sheet. So, as a starting point I tried to calculate the adsorption energy of hydrogen on boron doped graphene. However, I am unable to obtain values close to those that
 were stated in papers with similar DFT calculations. Does anyone have any suggestions as to what I might be doing incorrectly? My calculated value was -0.74 eV (please refer to below for input file used) while other papers stated -0.014 eV. I've tried different
 orientations for the hydrogen molecule (vertical vs horizontal to the graphene sheet) but my final value doesn't change by much (~0.01eV).<br>
<br>
  &control<br>
    prefix='h2ads_BG'<br>
    calculation='relax'<br>
    outdir = './out' <br>
    pseudo_dir = '/scratch/Hydrogen_Adsorption/pseudo/' <br>
    forc_conv_thr=1D-3<br>
 /<br>
 &system    <br>
    ibrav=0, nat=34, ntyp=3,<br>
    ecutwfc=25, ecutrho=200<br>
    occupations='smearing', smearing='methfessel-paxton', degauss=0.01<br>
 /<br>
 &electrons<br>
    mixing_mode='local-TF'<br>
 /<br>
 &ions<br>
 /<br>
CELL_PARAMETERS<br>
18.65816237 0.000000000 0.000000000<br>
9.329081185 16.15844260 0.000000000<br>
0.000000000 0.000000000 28.34588983<br>
ATOMIC_SPECIES<br>
 C 12.01  C.pbe-van_bm.UPF<br>
 H 1.001  H.pbe-van_bm.UPF<br>
 B 10.81  B.pbe-n-van.UPF<br>
ATOMIC_POSITIONS angstrom<br>
 C         1.728024        0.709000        0.001000<br>
 C         4.184072        0.709000        0.001000<br>
 C         6.640120        0.709000        0.001000<br>
 C         9.096169        0.709000        0.001000<br>
 C         1.728024        2.127000        0.001000<br>
 C         4.184072        2.127000        0.001000<br>
 C         6.640120        2.127000        0.001000<br>
 C         9.096169        2.127000        0.001000<br>
 C         2.931405        2.793323        0.001000<br>
 C         5.436735        2.793328        0.001000<br>
 C         7.892783        2.793323        0.001000<br>
 C        10.324192        2.793323        0.001000<br>
 C         2.956048        4.254000        0.001000<br>
 C         5.412096        4.254000        0.001000<br>
 B         7.868144        4.254000        0.001000<br>
 H         7.483935        4.254000        1.220000<br>
 H         8.252353        4.254000        1.220000<br>
 C        10.324192        4.254000        0.001000<br>
 C         4.184072        4.963000        0.001000<br>
 C         6.640120        4.963000        0.001000<br>
 C         9.096169        4.963000        0.001000<br>
 C        11.601494        4.963000        0.001000<br>
 C         4.184072        6.381000        0.001000<br>
 C         6.640120        6.381000        0.001000<br>
 C         9.096169        6.381000        0.001000<br>
 C        11.601494        6.381000        0.001000<br>
 C         5.412096        7.090000        0.001000<br>
 C         7.868144        7.090000        0.001000<br>
 C        10.373470        7.090000        0.001000<br>
 C        12.829518        7.090000        0.001000<br>
 C         5.412096        8.508000        0.001000<br>
 C         7.868144        8.508000        0.001000<br>
 C        10.373470        8.508000        0.001000<br>
 C        12.829518        8.508000        0.001000<br>
K_POINTS automatic<br>
5 5 1 1 1 1 <br>
<br>
Thank you all in advance.<br>
<br>
Regards,<br>
Janet Wong<br>
Graduate Student<br>
University of Toronto<br>
Canada</div>
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