<html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:st2="urn:schemas:contacts" xmlns:st1="urn:schemas-microsoft-com:office:smarttags" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 11 (filtered medium)">
<o:SmartTagType namespaceuri="urn:schemas:contacts" name="title"/>
<o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags"
name="PersonName" downloadurl="http://www.microsoft.com"/>
<o:SmartTagType namespaceuri="urn:schemas:contacts" name="Sn"/>
<!--[if !mso]>
<style>
st2\:*{behavior:url(#default#ieooui) }st1\:*{behavior:url(#default#ieooui) }
</style>
<![endif]-->
<style>
<!--
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman";}
a:link, span.MsoHyperlink
{color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Times New Roman";
color:windowtext;
font-weight:normal;
font-style:normal;
text-decoration:none none;}
@page Section1
{size:8.5in 11.0in;
margin:1.0in 1.25in 1.0in 1.25in;}
div.Section1
{page:Section1;}
-->
</style>
</head>
<body lang=EN-US link=blue vlink=purple>
<div class=Section1>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'>Dear Dr.Blaha, <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'>I am sorry I have posted this question before. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'>I guess my querie may be inappropriate in the Wien2k mailing list.
Still, first I would request <st1:PersonName w:st="on"><st2:title w:st="on">Prof.</st2:title>
<st2:Sn w:st="on">Blaha</st2:Sn></st1:PersonName> to kindly give me permission
and help me in sorting the issue in PHONON which actually is not a Wien2k
problem. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'>After I imported the case.dsy file ( forces convergence obtained with
0.005 mRy) in phonon software and incorporated the lattice parameters of the
supercell and the number of atoms, I applied the translational and
rotational invariances, I get the Do Report in PHONON. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'>I get the plot of force constants and I subsequently get the phonon
dispersion. I get some imaginary frequencies which I am not sure if it is because
of the wrong choice of supercell size (12 atoms) or the force convergence
(0.005 mRy/atom) <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'>Can you please help me in this regard? <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'>Can I send you the case.dsy for your perusal? <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'>Thank you <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'>Suddhasattwa <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face="Times New Roman"><span style='font-size:
11.0pt'><o:p> </o:p></span></font></p>
</div>
</body>
</html>