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</o:shapelayout></xml><![endif]--></head><body lang=ZH-CN link="#0563C1" vlink="#954F72" style='word-wrap:break-word;text-justify-trim:punctuation'><div class=WordSection1><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span lang=EN-US>Dear QE-Users,<br><br>I am planning to do some CPMD simulation about iron oxides (Fe2O3, Fe3O4 and FeO) and their reactions with hydrogen at high temperature using cp.x of QE 7.0. <br><br>As it is well known that spin and magnetism are the most fundamental characteristics for iron and its oxides, we should consider them (spin and magnetism) and add U in many cases for ‘scf’ or ‘relax’/’vc-relax’ calculations with pw.x. But it seems that considering spin, magnetism and U will make things more complicated and significantly increase the computation time, I am wondering whether it is acceptable to neglect spin, magnetism and U for CPMD simulation of iron oxides (Fe2O3, Fe3O4 and FeO) and their reactions with Hydrogen gas. My goal is only to try to simulation the reduction process in atomistic scale, and the CPMD trajectory results are sufficient to capture the reduction mechanism while the accuracy of band gap, magnetism is not the focus of my study.<br><br>Any comments or suggestions will be much appreciated.<br><br>Thanks,<br>Kejiang</span><b><span lang=EN-US style='font-size:11.0pt'><br><br></span></b><span lang=EN-US>-------------------------------------------------<br></span><span lang=EN-US style='font-size:9.0pt'>Dr. Kejiang Li<br>School of Metallurgical and Ecological Engineering,<br>University of Science and Technology Beijing<br>Xueyuan Rd., Haidian District, Beijing 100083, P. R. China</span><span lang=EN-US style='font-size:7.5pt'><br><a href="https://kejiangli.com/" target="_blank">https://kejiangli.com/</a></span><span lang=EN-US style='font-size:9.0pt'><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></body></html>