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    <div class="moz-cite-prefix">yes and no.<br>
      <br>
      By default the computed stress is the derivative of the energy at
      constant number of PW and the Pulay stress is not estimated.<br>
      You should check the PW basis is large enough that the stress is
      converged (hence Pulay stress is negligible). <br>
      An alternative is to use the smooth-cutoff trick implemented by
      the variables<br>
      ECFIXED, QCUTZ,Q2SIGMA (in the &system namelist)<br>
      See M. Bernasconi et al, J. Phys. Chem. Solids 56, 501 (1995),<br>
      doi:10.1016/0022-3697(94)00228-2 for an explanation<br>
      <br>
      stefano<br>
               <br>
      <br>
      On 22/03/2017 12:30, Umesh Roy wrote:<br>
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          <div>Dear Q.E users,<br>
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             Does the Q.E code calculate Pulay stress?<br>
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        Thank you all.<br clear="all">
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                                          <div><span
                                              style="color:rgb(0,0,255)"><span
style="background-color:rgb(243,243,243)"><i><b><br>
                                                    <br>
                                                    <br>
                                                    <br>
                                                    <br>
---------------------------------------------------------------------<br>
                                                    <br>
                                                    Umesh Chandra Roy</b><br>
                                                  Research Scholar<span></span>,
                                                  School of Physical
                                                  Sciences<br>
                                                  Jawaharlal Nehru
                                                  University, New
                                                  Delhi-110067,<br>
                                                </i></span></span></div>
                                          <div><span
                                              style="color:rgb(0,0,255)"><span
style="background-color:rgb(243,243,243)"><i>India.<br>
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                                                        style="color:rgb(0,0,255)">Email</span>:</font><b>umesh24crp@gmail.com</b></a><span></span><br>
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style="background-color:rgb(243,243,243)"><i>Mobile:<b>+919868022722</b></i></span></span></div>
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      <pre wrap="">_______________________________________________
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