<html>
  <head>
    <meta content="text/html; charset=windows-1252"
      http-equiv="Content-Type">
  </head>
  <body bgcolor="#FFFFFF" text="#000000">
    <div class="moz-cite-prefix">It is recommended to make both your
      slab surfaces identical where possible. The p21, p22 and p24 refer
      to the type of supercell used to represent the surface. Since you
      are using a periodic model you are imposing a strong symmetry on
      the surface, not all reconstructions can be made within your unit
      cell, indeed for your dimer you will need a 2x1 expansion, i.e.
      two cells next to eachother along the a axis. The symbols (and
      possible angles) represent the shape and rotation of the resulting
      cell (in this case p=primitive, c=centered).<br>
      <br>
      You can find more info in for instance: <br>
      Introduction to Solid State Physics - Kittel - about the
      description of cells<br>
      and <br>
      Density Functional Theory: A Practical Introduction - Sholl and
      Steckel  - for the basics of how to model surfaces<br>
      <br>
      Muhammad Sajjad schreef op 27/07/2015 om 10:51:<br>
    </div>
    <blockquote
cite="mid:CA+9d70XDUrQVwZknxf=LNMaxdv8bTiUTkY3Pn+Bw5PghbfyJDg@mail.gmail.com"
      type="cite">
      <div dir="ltr">
        <div>
          <div>
            <div>Dear Delamora and Michael<br>
            </div>
            Many thanks for informative suggestions. <br>
          </div>
           I am intended to study electronic properties of Si (100) of
          thickness 1 nm. I am asked to introduce dimers instead of
          using H. But my question is "one surface of the Si 100 must be
          passivated by hydrogen or not?"Like If ones introduce dimer on
          the top (maximum Z) then bottom (minimum Z) must be passivated
          or not? Can we introduce dimers on both surfaces (top &
          bottom). I am reading the paper ( <a moz-do-not-send="true"
            href="http://pubs.acs.org/doi/pdf/10.1021/jp509095t">http://pubs.acs.org/doi/pdf/10.1021/jp509095t</a>
          ). What does it means P21, P22, P24 reconstructions? <br>
           <br>
        </div>
        Many thanks <br>
        <br>
      </div>
      <div class="gmail_extra"><br>
        <div class="gmail_quote">On Sun, Jul 26, 2015 at 10:51 PM,
          Michael Sluydts <span dir="ltr"><<a moz-do-not-send="true"
              href="mailto:michael.sluydts@ugent.be" target="_blank">michael.sluydts@ugent.be</a>></span>
          wrote:<br>
          <blockquote class="gmail_quote" style="margin:0 0 0
            .8ex;border-left:1px #ccc solid;padding-left:1ex">
            <div bgcolor="#FFFFFF" text="#000000">
              <div>Muhammad,<br>
                <br>
                When you move the two Si atoms with the dangling bond
                towards eachother you will create a dimer on the
                surface, no extra passivation by H atoms is needed, just
                ensure you make your slab symmetric where possible. If
                you google Si recontructions you should find very exact
                geometrical information since this has been done many
                times before.<br>
                <br>
                Best regards,<br>
                <br>
                Michael Sluydts<br>
                <br>
                Muhammad Sajjad schreef op 26/07/2015 om 17:59:<br>
              </div>
              <div>
                <div class="h5">
                  <blockquote type="cite">
                    <div dir="ltr">
                      <div>Thank you Pablo<br>
                      </div>
                      But I am required to connect two Si atoms at the
                      surface to reduce one dangling bond and then put H
                      or may be H is not needed if both of the dangling
                      bonds have possibility of omitting. I am reading
                      the paper but could not understand although Fig. 2
                      is looking easy to understand. WHat is 2*1 or 2*2
                      or 2*4 ? are the super-cells like 2*1*1 or 2*2*1
                      etc.<br>
                      <br>
                    </div>
                    <div class="gmail_extra"><br>
                      <div class="gmail_quote">On Sun, Jul 26, 2015 at
                        6:22 PM, delamora <span dir="ltr"><<a
                            moz-do-not-send="true"
                            href="mailto:delamora@unam.mx"
                            target="_blank">delamora@unam.mx</a>></span>
                        wrote:<br>
                        <blockquote class="gmail_quote" style="margin:0
                          0 0 .8ex;border-left:1px #ccc
                          solid;padding-left:1ex">
                          <div dir="ltr">
                            <div
style="font-size:12pt;color:#000000;background-color:#ffffff;font-family:Calibri,Arial,Helvetica,sans-serif">
                              <p>This is the same that I simplified and
                                symmetized. If you are going to add H
                                then you need set the space group as P1
                                (#1) so the H can move freely and not in
                                a symmetrical path.</p>
                              <p>Now, if you use my proposed structure
                                then you can put inversion (SG P-1, #2)
                                and add two H, one on each surface, but
                                in a symmetric way.</p>
                              <p>Other thing, maybe my proposed
                                structure is too small and your
                                structure is ok, but I would symmetrize
                                as I explained in an earlier message. <br>
                              </p>
                              <br>
                                                     Pablo<br>
                              <div style="color:rgb(0,0,0)">
                                <hr
                                  style="display:inline-block;width:98%">
                                <div dir="ltr"><font
                                    style="font-size:11pt"
                                    color="#000000" face="Calibri,
                                    sans-serif"><b>De:</b> <a
                                      moz-do-not-send="true"
                                      href="mailto:wien-bounces@zeus.theochem.tuwien.ac.at"
                                      target="_blank">wien-bounces@zeus.theochem.tuwien.ac.at</a>
                                    <<a moz-do-not-send="true"
                                      href="mailto:wien-bounces@zeus.theochem.tuwien.ac.at"
                                      target="_blank">wien-bounces@zeus.theochem.tuwien.ac.at</a>>

                                    en nombre de Muhammad Sajjad <<a
                                      moz-do-not-send="true"
                                      href="mailto:sajjadpu@gmail.com"
                                      target="_blank">sajjadpu@gmail.com</a>><br>
                                    <b>Enviado:</b> domingo, 26 de julio
                                    de 2015 04:44 a. m.<br>
                                    <b>Para:</b> wien<br>
                                    <b>Asunto:</b> [Wien] Reconstructed
                                    Si 100 surface</font>
                                  <div> </div>
                                </div>
                                <div>
                                  <div>
                                    <div>
                                      <div dir="ltr">
                                        <div>Dear Users<br>
                                        </div>
                                        Kindly guide me how to
                                        reconstruct Si 100 layer? The Si
                                        100 structure is attached here
                                        with. It has two dangling bonds
                                        on both surfaces (Top and
                                        Bottom). My intension is to keep
                                        one dangling bond on the top and
                                        bottom surfaces that will be
                                        saturated by H addition.  <br>
                                        <div>
                                          <div>
                                            <div>-- <br>
                                              <div>
                                                <div dir="ltr">
                                                  <div>Kind Regards</div>
                                                  <div>Muhammad Sajjad </div>
                                                  <div>Post Doctoral
                                                    Fellow</div>
                                                  <div>KAUST, KSA.</div>
                                                </div>
                                              </div>
                                            </div>
                                          </div>
                                        </div>
                                      </div>
                                    </div>
                                  </div>
                                </div>
                              </div>
                            </div>
                          </div>
                          <br>
_______________________________________________<br>
                          Wien mailing list<br>
                          <a moz-do-not-send="true"
                            href="mailto:Wien@zeus.theochem.tuwien.ac.at"
                            target="_blank">Wien@zeus.theochem.tuwien.ac.at</a><br>
                          <a moz-do-not-send="true"
                            href="http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien"
                            rel="noreferrer" target="_blank">http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien</a><br>
                          SEARCH the MAILING-LIST at:  <a
                            moz-do-not-send="true"
href="http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html"
                            rel="noreferrer" target="_blank">http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html</a><br>
                          <br>
                        </blockquote>
                      </div>
                      <br>
                      <br clear="all">
                      <br>
                      -- <br>
                      <div>
                        <div dir="ltr">
                          <div>Kind Regards</div>
                          <div>Muhammad Sajjad </div>
                          <div>Post Doctoral Fellow</div>
                          <div>KAUST, KSA.</div>
                        </div>
                      </div>
                    </div>
                    <br>
                    <fieldset></fieldset>
                    <br>
                    <pre>_______________________________________________
Wien mailing list
<a moz-do-not-send="true" href="mailto:Wien@zeus.theochem.tuwien.ac.at" target="_blank">Wien@zeus.theochem.tuwien.ac.at</a>
<a moz-do-not-send="true" href="http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien" target="_blank">http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien</a>
SEARCH the MAILING-LIST at:  <a moz-do-not-send="true" href="http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html" target="_blank">http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html</a>
</pre>
                  </blockquote>
                  <br>
                  <br>
                </div>
              </div>
              <span class="HOEnZb"><font color="#888888">
                  <pre cols="72">-- 
ir. Michael Sluydts
Center for Molecular Modeling
Ghent University
Technologiepark 903
9052 Zwijnaarde, Belgium
tel. +32 (0)9 264 66 19
<a moz-do-not-send="true" href="https://molmod.ugent.be" target="_blank">https://molmod.ugent.be</a></pre>
                </font></span></div>
            <br>
            _______________________________________________<br>
            Wien mailing list<br>
            <a moz-do-not-send="true"
              href="mailto:Wien@zeus.theochem.tuwien.ac.at">Wien@zeus.theochem.tuwien.ac.at</a><br>
            <a moz-do-not-send="true"
              href="http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien"
              rel="noreferrer" target="_blank">http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien</a><br>
            SEARCH the MAILING-LIST at:  <a moz-do-not-send="true"
href="http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html"
              rel="noreferrer" target="_blank">http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html</a><br>
            <br>
          </blockquote>
        </div>
        <br>
        <br clear="all">
        <br>
        -- <br>
        <div class="gmail_signature">
          <div dir="ltr">
            <div>Kind Regards</div>
            <div>Muhammad Sajjad </div>
            <div>Post Doctoral Fellow</div>
            <div>KAUST, KSA.</div>
          </div>
        </div>
      </div>
      <br>
      <fieldset class="mimeAttachmentHeader"></fieldset>
      <br>
      <pre wrap="">_______________________________________________
Wien mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Wien@zeus.theochem.tuwien.ac.at">Wien@zeus.theochem.tuwien.ac.at</a>
<a class="moz-txt-link-freetext" href="http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien">http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien</a>
SEARCH the MAILING-LIST at:  <a class="moz-txt-link-freetext" href="http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html">http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html</a>
</pre>
    </blockquote>
    <br>
    <br>
    <pre class="moz-signature" cols="72">-- 
ir. Michael Sluydts
Center for Molecular Modeling
Ghent University
Technologiepark 903
9052 Zwijnaarde, Belgium
tel. +32 (0)9 264 66 19
<a class="moz-txt-link-freetext" href="https://molmod.ugent.be">https://molmod.ugent.be</a></pre>
  </body>
</html>