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<div><div>Dear everyone, </div><div> </div><div> I have two questions about the computation about Quantum Espresso. </div><div><br></div><div> The first question is about the pseudopotential aout "O.pbe-n-kjpaw_psl.0.1.UPF". I don't understand why the config setting is [He] 2S2 2P4 3d-2 rather than [He] 2S2 2P4 in the part of <pp_INPUTFILE>? What is the meaning of 3d-2?</div><div> </div><div> The second question is about calculating the mometum matrix between conduction and valence bands. I write "lp = .true." into the input file shown as below:</div><div> # &control</div><div> calculation = 'bands'</div><div> restart_mode='from_scratch'</div><div> prefix = 'si'</div><div> outdir = './outdir'</div><div> pseudo_dir = '/home/jingjing/software/qe-7.0-ReleasePack/qe-7.0/pseudo'</div><div>/</div><div>&system</div><div> ibrav=2, celldm(1) =10.410909236, </div><div> nat=2, ntyp=1,</div><div> ecutwfc=40</div><div> ecutrho=320</div><div> nbnd=8</div><div>/</div><div>&electrons</div><div> conv_thr=1e-8</div><div>/</div><div>ATOMIC_SPECIES</div><div> Si 28.0855 Si.pbe-n-rrkjus_psl.1.0.0.UPF</div><div><br></div><div>ATOMIC_POSITIONS (alat)</div><div> Si 0.00 0.00 0.00</div><div> Si 0.25 0.25 0.25</div><div>K_POINTS {crystal_b}</div><div>5</div><div> 0.0000 0.5000 0.0000 20 !L</div><div> 0.0000 0.0000 0.0000 30 !Gamma</div><div> -0.500 0.0000 -0.500 10 !X</div><div> -0.375 0.2500 -0.375 30 !U</div><div> 0.0000 0.0000 0.0000 20 !Gamma #</div><div><br></div><div>#&bands</div><div> outdir='./outdir/'</div><div> prefix='si'</div><div> filband='si.bands.dat'</div><div> lp=.true.</div><div> filp = 'p_avg.dat'</div><div>/</div><div>#</div><div><br></div><div><br></div><div> And the file named p_avg.dat was created and the content is shown below:</div><div>#</div><div> &p_mat nbnd= 8, nks= 91 /</div><div> 0.500000 0.500000 0.500000 4</div><div> 1</div><div> 0.00813521 0.00000000 0.15416532 0.07417279</div><div> 0.00711204 0.00000000 0.07396118 0.07519155</div><div> 0.00395441 0.00000000 0.07817072 0.04482350</div><div> 0.00000000 0.00136338 0.00000000 0.00000000</div><div> 2</div><div> 0.00813521 0.00000000 0.17497626 0.05336175</div><div> 0.00365900 0.00000000 0.02680065 0.09374623</div><div> 0.00740747 0.00000000 0.13368684 0.01791326</div><div> 0.00000000 0.00136324 0.00000000 0.00000000</div><div> 3</div><div> 0.00813521 0.00000000 0.01336552 0.21497263</div><div> 0.00582865 0.00000000 0.02094852 0.11757237</div><div> 0.00523781 0.00000000 0.07465264 0.05897362</div><div> 0.00000000 0.00136330 0.00000000 0.00000000</div><div><br></div><div> ....</div><div># </div><div> I think that the (0.500000 0.500000 0.500000) and number 4 in the second line represents the symmetric k point and number of valence band. But I don't know the what the number 1, 2, 3 represents located in the line3, 8 and 13 respectively? And could someone tell me what the meaning of 4x4 matrix is? </div><div> I guess it should be the momentum matrix, the value_11 (the value located in the first row and the first column ) means the momentum matrix between the first valence band(from top to bottom direction) and the first conduction band (from the bottom to the top direction)? if it was true, for every k point, it should have 16 values of momentum matrix-4 x 4 matrix, as there are 4 valence bands and 4 conduction bands. But why there are 3 series of 4x4 mometume matrix?</div><div> I tried to find some introduction about explaning the p_avg.dat file, but there is almost no reference. So it is very appreciated that someone could provide more details about calculating the mometum matrixs in QE software.</div><div><br></div><div> Thank you very much!</div><div><br></div><div> Best regards,</div><div> Jingjing</div></div>
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<div style="color: rgb(49, 53, 59); line-height: 22.4px;">--</div><div style="color: rgb(49, 53, 59); line-height: 22.4px;">M.Sc. Jingjing Yu<div><span style="background-color: rgb(255, 255, 255);"><span style="font-family: Arial, Helvetica, sans-serif; font-variant-ligatures: normal; orphans: 2; widows: 2;">Universität Leipzig</span><br style="font-family: Arial, Helvetica, sans-serif; font-variant-ligatures: normal; orphans: 2; widows: 2;"><span style="font-family: Arial, Helvetica, sans-serif; font-variant-ligatures: normal; orphans: 2; widows: 2;">Felix-Bloch-Institut für Festkörperphysik</span><br style="font-family: Arial, Helvetica, sans-serif; font-variant-ligatures: normal; orphans: 2; widows: 2;"><span style="font-family: Arial, Helvetica, sans-serif; font-variant-ligatures: normal; orphans: 2; widows: 2;">Halbleiterphysik</span><br style="font-family: Arial, Helvetica, sans-serif; font-variant-ligatures: normal; orphans: 2; widows: 2;"><span style="font-family: Arial, Helvetica, sans-serif; font-variant-ligatures: normal; orphans: 2; widows: 2;">Linnéstraße 5</span><br style="font-family: Arial, Helvetica, sans-serif; font-variant-ligatures: normal; orphans: 2; widows: 2;"><span style="font-family: Arial, Helvetica, sans-serif; font-variant-ligatures: normal; orphans: 2; widows: 2;">04103 Leipzig, Germany</span></span></div></div>
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