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</o:shapelayout></xml><![endif]--></head><body lang=ZH-CN link="#0563C1" vlink="#954F72" style='text-justify-trim:punctuation'><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:10.5pt'>Dear all,<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>In tests a normal DFT calculations with Si, I noticed that QE 6.0 and 6.1 gives exactly same total energy with 6.0 and 6.1 (-15.75190880 Ry), but with QE 6.2.1, the total energy is -15.75191309Ry. I tested this on two different machines with different compilers, the results are the same across all of them (at least to last digit). I did some tests on larger systems also and found even larger difference. This 1e-5 Ry order of difference is not negligible. Is there anything introduced in 6.2 leads to this difference? Thanks very much.<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.5pt'>Best regards,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.5pt'>Feng<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'><o:p> </o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>The input file is attached:<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>====================<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>&control<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> calculation='scf'<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> outdir='./tmp'<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> prefix='si'<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> wf_collect = .true.,<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>/<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> &system<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> ibrav=2,<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> celldm(1) = 10.263,<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> nat=2,<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> ntyp= 1,<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> ecutwfc = 40,<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>/<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> &electrons<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> mixing_mode='plain'<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> mixing_beta = 0.7,<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> conv_thr = 1.0d-10,<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'> /<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>ATOMIC_SPECIES<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>Si 1.0 Si_ONCV_PBE-1.1.upf<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>ATOMIC_POSITIONS {alat}<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>Si 0.00 0.00 0.00<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>Si 0.25 0.25 0.25<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>K_POINTS (automatic)<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>4 4 4 0 0 0<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'>==============<o:p></o:p></span></p><p class=MsoNormal style='text-indent:21.0pt'><span lang=EN-US style='font-size:10.5pt'><o:p> </o:p></span></p><p class=MsoNormal style='text-align:justify;text-justify:inter-ideograph'><span lang=EN-US style='font-size:10.5pt'><o:p> </o:p></span></p><p class=MsoNormal style='text-align:justify;text-justify:inter-ideograph'><span lang=EN-US style='font-size:10.5pt'>--------------------------------------------------<o:p></o:p></span></p><p class=MsoNormal style='text-align:justify;text-justify:inter-ideograph'><span lang=EN-US style='font-size:10.5pt'>Dr. Feng Wu<o:p></o:p></span></p><p class=MsoNormal style='text-align:justify;text-justify:inter-ideograph'><span lang=EN-US style='font-size:10.5pt'>Postdoctoral researcher<o:p></o:p></span></p><p class=MsoNormal style='text-align:justify;text-justify:inter-ideograph'><span lang=EN-US style='font-size:10.5pt'>Department of Chemistry and Biochemistry<o:p></o:p></span></p><p class=MsoNormal style='text-align:justify;text-justify:inter-ideograph'><span lang=EN-US style='font-size:10.5pt'>University of California, Santa Cruz<o:p></o:p></span></p><p class=MsoNormal style='text-align:justify;text-justify:inter-ideograph'><span lang=EN-US style='font-size:10.5pt'>Phone: 831-459-2874<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:10.5pt'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p></div></body></html>