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</o:shapelayout></xml><![endif]--></head><body lang=DE link="#467886" vlink="#96607D" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;mso-fareast-language:EN-US'>Hello,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;mso-fareast-language:EN-US'>the wavefunction coefficients are saved in the wfc*.dat files in a binary format. Each k-point has its own wfc*.dat file.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;mso-fareast-language:EN-US'>These dat files can be read with python, which is explained here: <a href="https://mattermodeling.stackexchange.com/questions/9149/how-to-read-qes-wfc-dat-files-with-python">https://mattermodeling.stackexchange.com/questions/9149/how-to-read-qes-wfc-dat-files-with-python</a><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;mso-fareast-language:EN-US'>A bit of self-advertisement: We build a python package for reading Quantum ESPRESSO output to generate a many-body Hamiltonian with exact Coulomb interaction: <a href="https://github.com/dlr-wf/Dopyqo/tree/main">Dopyqo</a><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;mso-fareast-language:EN-US'> With Dopyqo you can read the wavefunction information with the provided <a href="https://github.com/dlr-wf/Dopyqo/blob/main/dopyqo/wfc.py">Wfc class</a>. Especially, use the <a href="https://github.com/dlr-wf/Dopyqo/blob/07232d2511071c7a5013029a321d7eceac890d85/dopyqo/wfc.py#L422C9-L422C18">from_file</a> and <a href="https://github.com/dlr-wf/Dopyqo/blob/07232d2511071c7a5013029a321d7eceac890d85/dopyqo/wfc.py#L633">from_file_all_kpoints</a> functions for that.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;mso-fareast-language:EN-US'>I hope that helps.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal style='line-height:14.0pt'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray;mso-fareast-language:AR-SA'>——————————————————————————</span><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'><o:p></o:p></span></p><p class=MsoNormal style='line-height:14.0pt'><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>#CallMeByMyFirstName<o:p></o:p></span></p><p class=MsoNormal style='punctuation-wrap:simple;text-autospace:none'><b><span style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-family:"Arial",sans-serif;color:dimgray;mso-fareast-language:AR-SA'>Deutsches Zentrum für Luft- und Raumfahrt</span></b><span style='color:dimgray'> e. V. (DLR)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:dimgray'>German Aerospace Center<o:p></o:p></span></p><p class=MsoNormal style='line-height:16.0pt;punctuation-wrap:simple;text-autospace:none'><span lang=EN-US style='font-size:8.5pt;font-family:"Arial",sans-serif;color:dimgray;mso-fareast-language:EN-GB'>Institute of Materials Research</span><span lang=EN-US style='font-size:8.5pt;font-family:"Arial",sans-serif;color:dimgray'> | Linder Höhe | 51147 Cologne</span><span lang=EN-US style='font-size:8.5pt;font-family:"Arial",sans-serif'><o:p></o:p></span></p><p class=MsoNormal style='punctuation-wrap:simple;text-autospace:none'><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal style='punctuation-wrap:simple;text-autospace:none'><b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>Erik Schultheis M. Sc. </span></b><span lang=EN-US style='font-size:10.0pt;font-family:"Arial",sans-serif;color:dimgray'>| Research assistant</span><span lang=EN-US style='font-size:8.5pt;font-family:"Arial",sans-serif;color:dimgray'><o:p></o:p></span></p><p class=MsoNormal style='line-height:16.0pt;punctuation-wrap:simple;text-autospace:none'><span lang=EN-US style='font-size:8.5pt;font-family:"Arial",sans-serif;color:dimgray'>Telephone: +49 (0) 2203 601 1311 | </span><span style='font-size:8.5pt;font-family:"Arial",sans-serif;color:dimgray'><a href="mailto:erik.schultheis@dlr.de"><span lang=EN-US>erik.schultheis@dlr.de</span></a></span><span lang=EN-US style='font-size:8.5pt;font-family:"Arial",sans-serif;color:dimgray'> | </span><span style='font-size:8.5pt;font-family:"Arial",sans-serif;color:dimgray'><a href="https://www.linkedin.com/in/erik-schultheis-930549243/"><span lang=EN-US>LinkedIn</span></a></span><span lang=EN-US style='font-size:8.5pt;font-family:"Arial",sans-serif;color:dimgray'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><a href="http://www.DLR.de/"><span lang=EN-US style='font-size:8.5pt'>DLR.de</span></a><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal style='text-autospace:none'><span lang=EN-US style='font-size:7.0pt;color:#737373'>DLR is represented by the Executive Board and employees authorised by it.<br>Head of DLR's legal department, Linder Hoehe, 51147 Cologne, can provide information (</span><a href="https://DLR.de/imprint"><span lang=EN-US style='font-size:7.0pt'>DLR.de/imprint</span></a><span lang=EN-US style='font-size:7.0pt;color:#737373'>).</span><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>Von:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> users <users-bounces@lists.quantum-espresso.org> <b>Im Auftrag von </b>???? via users<br><b>Gesendet:</b> Samstag, 15. November 2025 08:56<br><b>An:</b> users <users@lists.quantum-espresso.org><br><b>Betreff:</b> [QE-users] how to read the plane wave coefficient of wavefunction?<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><span style='font-size:14.0pt;font-family:"Times New Roman",serif;color:black'>Dear,<o:p></o:p></span></p></div><div style='margin-left:21.0pt'><p class=MsoNormal><span style='font-size:14.0pt;font-family:"Times New Roman",serif;color:black'>I'm trying to extract the plane wave expansion coefficients of the wavefunction ψₙₖ, where n is the band index and k is the k-point index. However, I'm unsure which files contain these coefficients and what their specific formats are. Could anyone provide some guidance?<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.5pt;font-family:"system-ui",serif;color:black'><o:p> </o:p></span></p></div></div></body></html>