<br><br><div class="gmail_quote">---------- Forwarded message ----------<br>From: <b class="gmail_sendername">bhabya sahoo</b> <span dir="ltr"><<a href="mailto:bdslipun@gmail.com">bdslipun@gmail.com</a>></span><br>Date: Thu, Dec 29, 2011 at 11:04 AM<br>
Subject: beta tin structure<br>To: PWSCF Forum <<a href="mailto:pw_forum@pwscf.org">pw_forum@pwscf.org</a>><br><br><br>i want the phonon dispersion curve for beta tin structure<div>so i gave the positions of atoms as primitive tetragonal structure having coordinates</div>
<div>0 0 0, .5 0 .25 , .5 .5 .5, 0 .5 .75 like 4a whychoff positions (c/a=.546)</div>
<div>so no of atoms is 4 in the unit cell so in phonon there will be 12 branches</div><div>but i have seen 6 branches so how can i put my primitive tetragonal structure having two atoms in unitcell</div><div>or in other way how can i give the input for beta tin structure </div>
<div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div><br></div><div>b d sahoo</div><div>reserch scholar</div><div>mumbai</div>
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