so if i have a 2-D system, say BN sheet, i have to model layers with more vaccum space in between them to extract the response ?<div><br><br><div class="gmail_quote">On Tue, Oct 11, 2011 at 3:57 PM, Stefano Baroni <span dir="ltr"><<a href="mailto:baroni@sissa.it">baroni@sissa.it</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"><div style="word-wrap:break-word">Dear Swapnil,<div><br></div><div>piezoelectricity is a bulk property. No supercells are needed.</div>
<div>See e.g.: </div><div>R.M. Martin, PRB 5, 1607 (1972), <span style="background-color:rgb(255, 255, 255)"><a href="http://link.aps.org/doi/10.1103/PhysRevB.5.1607" target="_blank">http://link.aps.org/doi/10.1103/PhysRevB.5.1607</a></span></div>
<div>S. de Gironcoli et al., <span style="line-height:18px">Phys. Rev. Lett. 62, 2853–2856 (1989), </span><span style="background-color:rgb(255, 255, 255)"><a href="http://link.aps.org/doi/10.1103/PhysRevLett.62.2853" target="_blank">http://link.aps.org/doi/10.1103/PhysRevLett.62.2853</a></span></div>
<div><span style="background-color:rgb(255, 255, 255)"><br></span></div><div><span style="background-color:rgb(255, 255, 255)">Regards, SB</span></div><div><br></div><div><font color="#323232" face="arial, helvetica, sans-serif"><span style="font-size:12px">, <br>
</span></font><div><div><div></div><div class="h5"><div>On Oct 11, 2011, at 6:47 PM, swapnil chandratre wrote:</div><br></div></div><blockquote type="cite"><div><div></div><div class="h5">Hi,<div><br></div><div>I want to understand the concept of piezoelectricity in Espresso, I have some doubts,</div>
<div><br></div><div>Is it necessary that in order to observe the phenomenon in direct manner (ie application of strain to get polarization), i need to create vaccum in the direction of polarization? or i can work with periordic systems, and observe polarization.?</div>
<div><br></div><div>With respect to the same, if i want to see the effect of field on length dimension of input geometry, I have to proceed with applying vaccum in that direction.? </div><div><br>Is my understanding of the approach incorrect ? can anyone help me understand it better.</div>
<div><div><br></div>-- <br>Regards,<br>Swapnil Chandratre<br>Graduate Student<br>Dept. of Mechanical Engineering,<br>University of Houston,<br>Houston, TX<br>(M)-<a href="tel:713-294-9546" value="+17132949546" target="_blank">713-294-9546</a><br>
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<br></blockquote></div><br><br clear="all"><div><br></div>-- <br>Regards,<br>Swapnil Chandratre<br>Graduate Student<br>Dept. of Mechanical Engineering,<br>University of Houston,<br>Houston, TX<br>(M)-713-294-9546<br>
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