There have been lot of studies on this system. I guess the structure is stable in certain range of strain. I suggest you do the calculations for a range of lattice constant, may be you will get the optimum one at which your structure will be stable. Below are the few references if you want to take a look.<br>
<br><h2><span style="font-weight:normal">Phys. Rev. B
76,
020102(R)
(2007)</span></h2><h2><span style="font-weight:normal">Appl. Phys. Lett. 87, 052903 (2005); <a href="http://link.aip.org/link/doi/10.1063/1.2006216">http://dx.doi.org/10.1063/1.2006216</a></span></h2>
<h2><span style="font-weight:normal">Appl. Phys. Lett. 91, 112914 (2007); <a href="http://link.aip.org/link/doi/10.1063/1.2785121">http://dx.doi.org/10.1063/1.2785121</a></span><br></h2><br><div class="gmail_quote">On Mon, Mar 18, 2013 at 8:42 AM, shruti shukla <span dir="ltr"><<a href="mailto:shruti_12912@rediffmail.com" target="_blank">shruti_12912@rediffmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Dear users,<br>
<br>
I am making an artificial superlattice (BaTiO3/SrTiO3). The total energy of superlattice is greater than the sum of the total energies of its two component lattices. Should I proceed with my calculations or not?<br>
<br>
Shruti<br><table style="font-family:Verdana;font-size:11px;line-height:15px" border="0" cellpadding="0" cellspacing="0" height="57" width="100%"><tbody><tr><td><a href="http://sigads.rediff.com/RealMedia/ads/click_nx.ads/www.rediffmail.com/signatureline.htm@Middle?" target="_blank"><img src=""></a></td>
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