<div dir="ltr"><div>Dear all</div><div>I am doing relaxation for a system of C, O, and H2 which should have a 3eV band gap. however, in my relaxation calculation, from the eigenvalues it shows no band gap. So, I cannot trust the further nmr reulst. after this step. I also paste my input for relax down, can anybody tell me what is the problem?</div>
<div>as seen:</div><div><span lang="EN-CA"><p> k = 0.0000 0.0000 0.0000 ( 74723 PWs) bands (ev):</p>
<p> -23.3453 -23.2509 -23.2259 -23.1667 -23.1380 -23.1122 -23.0976 -23.0482</p>
<p> -23.0458 -23.0391 -23.0106 -22.9744 -22.9539 -22.8721 -22.8682 -22.8455</p>
<p> -22.3021 -22.2631 -22.2033 -22.1970 -22.1484 -22.1315 -22.1282 -22.0954</p>
<p> -22.0871 -22.0694 -22.0552 -22.0311 -22.0123 -21.9204 -21.9035 -21.8837</p>
<p> -8.4344 -8.3878 -8.3473 -8.3270 -8.3022 -8.2845 -8.2588 -8.2276</p>
<p> -8.1713 -8.1558 -8.1257 -8.1136 -8.0572 -8.0456 -8.0142 -7.8924</p>
<p> -7.6997 -7.6605 -7.6189 -7.5822 -7.5252 -7.4844 -7.4585 -7.4155</p>
<p> -7.3812 -7.3456 -7.3208 -7.2927 -7.2727 -7.2064 -7.1959 -7.1331</p>
<p> -7.0934 -7.0671 -7.0557 -7.0208 -7.0045 -6.9641 -6.9386 -6.8821</p>
<p> -6.8590 -6.8208 -6.7835 -6.7601 -6.7139 -6.6954 -6.6775 -6.6429</p>
<p> -6.6383 -6.6099 -6.5706 -6.5443 -6.5219 -6.4977 -6.4694 -6.4132</p>
<p> -6.3866 -6.3671 -6.3464 -6.3133 -6.2895 -6.2532 -6.2271 -6.1256</p>
<p> -5.3074 -5.0504 -4.9293 -4.8727 -4.7052 -4.6028 -4.5628 -4.4287</p>
<p> -4.3984 -4.2942 -4.2714 -4.1638 -4.0900 -4.0423 -3.9205 -3.8424</p>
<p> -3.5850 -3.5379 -3.5217 -3.4738 -3.4482 -3.4294 -3.4036 -3.3727</p>
<p> -3.3479 -3.3346 -3.3131 -3.2836 -3.2617 -3.2478 -3.2094 -3.2018</p>
<p> -3.1871 -3.1527 -3.1299 -3.1174 -3.0990 -3.0931 -3.0428 -3.0157</p>
<p> -2.9912 -2.9617 -2.9398 -2.9352 -2.8936 -2.8767 -2.8479 -2.8174</p></span></div><div> </div><span lang="EN-CA"><p> &CONTROL</p><div>
</div><p> calculation = 'relax'</p><div>
</div><p> restart_mode = 'from_scratch'</p><div>
</div><p> prefix = 'CO2-H2-recover_product_nmr'</p><div>
</div><p> tstress = .true.</p><div>
</div><p> tprnfor = .true.</p><div>
</div><p> nstep=500,</p><div>
</div><p> dt=50,</p><div>
</div><p> pseudo_dir = './'</p><div>
</div><p> outdir = './scratch/' </p><div>
</div><p> /</p><div>
</div><p> &SYSTEM</p><div>
</div><p> ibrav = 0 </p><div>
</div><p> celldm(1) = 1.889726164</p><div>
</div><p> nat = 80</p><div>
</div><p> ntyp = 3</p><div>
</div><p> ecutwfc = 80.000 </p><div>
</div><p> ecutrho = 800.0</p><div>
</div><p> nosym = .true. </p><div>
</div><p> /</p><div>
</div><p> &electrons</p><div>
</div><p> mixing_beta = 0.7</p><div>
</div><p> conv_thr = 1.0d-8</p><div>
</div><p> /</p><div>
</div><p> &IONS</p><div>
</div><p> ion_dynamics='bfgs'</p><div>
</div><p> upscale=20,</p><div>
</div><p> /</p><div>
</div><p>CELL_PARAMETERS alat</p><div>
</div><p> 9.9705270608830947 -0.0263506434352082 -0.3371859913906344</p><div>
</div><p> -0.0182095492082954 8.1336917725945508 -0.3120449570661378</p><div>
</div><p> -0.4215858584102301 -0.4581954945537299 11.3361129017285922</p><div>
</div><p>ATOMIC_SPECIES</p><div>
</div><p> H 1.00000 H.pbe-tm-gipaw.UPF </p><div>
</div><p> C 12.00000 C.pbe-tm-gipaw.UPF</p><div>
</div><p> O 16.00000 O.pbe-tm-gipaw.UPF</p><div>
</div><p>ATOMIC_POSITIONS crystal</p></span><div><br clear="all">thanks in advance</div><div> </div><div>Xue<br>-- <br></div><div>Ms. Xue Yong(雍雪)<br>Department of Physics and Engineering Physics<br>University of Saskatchewan<br>
116 Science Place<br>Saskatoon, SK S7N 5E2<br>Canada</div><div>Tel: +1 306 261 2369</div>
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