Thank you, Paolo. I will read that :)<br>
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        -----原始邮件-----<br>
<b>发件人:</b><span id="rc_from">"Paolo Giannozzi" <p.giannozzi@gmail.com></span><br>
<b>发送时间:</b><span id="rc_senttime">2020-06-06 23:38:30 (星期六)</span><br>
<b>收件人:</b> "Quantum ESPRESSO users Forum" <users@lists.quantum-espresso.org><br>
<b>抄送:</b> <br>
<b>主题:</b> Re: [QE-users] fundamental questions about force convergence criterion<br>
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                        On Sat, Jun 6, 2020 at 5:18 PM <<a href="mailto:ykhuang@dicp.ac.cn">ykhuang@dicp.ac.cn</a>> wrote:
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                                    1. What do two lines below "<span style="font-family:SimSun;white-space:normal;">Forces acting on atoms...</span>" mean?
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                                they are exactly what it is printed on output: "Forces acting on atoms"
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                                I tried to add all "contribution" terms (from non-local to dispersion) of one atom together but found not to equal to 0.00001085.
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                                there might be some contribution that is not printed on output. Those that are printed are the main contributions. You find all of them in PW/src/forces.f90. It is quite readable because there is a separate routine for each contribution
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                                Paolo<br>
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                                                        Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,<br>
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy<br>
Phone +39-0432-558216, fax +39-0432-558222<br>
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