<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto"><div><span></span></div><div><div><div style="direction: inherit;">A good message is made by: a meaningful subject, a body, name and affiliation.</div><div style="direction: inherit;"><br></div><div style="direction: inherit;">This being said, if I can understand the subject of your message, it is possibile to study a quantum dot with Quantum-Espresso. Vacuum Space is needed to avoid periodic replica from interacting with each other. Let's suppose, just to make an example, you have a nearly spherical quantum dot, with radius R, you can setup a cubic unit cell with size a=R+V, where V is the vacuum space size. For quantum dots you can use gamma only k-point sampling, because if your calculation is properly done, no dispersion should show up (flat bands, corresponding to a confined system). Convergence with respect to V must be checked. </div><div style="direction: inherit;"><br></div><div style="direction: inherit;">I suggest to read relevant literature, to browse QE web site and tutorials, where lot of information that might be of interest for you is found.</div><div style="direction: inherit;"><br></div><div style="direction: inherit;">Giovanni</div><div style="direction: inherit;"><br></div>Inviato da iPad</div><div><br>Il giorno 20 feb 2017, alle ore 21:19, ali mehdizadeh <<a href="mailto:ali.mehdizadeh.physics1992@gmail.com">ali.mehdizadeh.physics1992@gmail.com</a>> ha scritto:<br><br></div><blockquote type="cite"><div><div dir="ltr"><br></div>
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