<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html;charset=UTF-8" http-equiv="Content-Type">
</head>
<body bgcolor="#ffffff" text="#000000">
<font face="Helvetica, Arial, sans-serif"><br>
The charge is not calculated at EFermi, but it is the sum of the charge
from the Kohn-Sham states integrated over the Brillouin zone and summed
from the lowest state to the EFermi. <br>
<br>
</font><font face="Helvetica, Arial, sans-serif">The integral over the
charge distribution (on your XSF grid) should equal "nelec" from PWSCF.</font>
<br>
<font face="Helvetica, Arial, sans-serif"><br>
The minimum and maximum value tells you the min. and max. value on the
XSF grid. So if you have a uniform charge concentration min=max. For
Si it is likely that 0.0014 will be located somewhere in an
interstitial region and 0.87 will be located in a bond-charge. <br>
<br>
I wouldn't say that there is any "ideal" isovalue. I would fiddle with
this value and look at the charge distribution. This will allow you to
develop qualitative picture of how your system works. <br>
<br>
<br>
<br>
<br>
</font><br>
Yamit wrote:
<blockquote
cite="mid:1280749023.S.1967.62380.webmail.rediff.com.drafts.1280750712.6288@webmail.rediffmail.com"
type="cite">Hello All<br>
<br>
I am using Xcrysden to plot charge density of Silicon (example 05:
Quantum Esspresso-4.2). <br>
*) Could anyone please tell the details of "xsf" file?<br>
( This charge density is calculated at Fermi Energy. Please also
correct me, if I am wrong.)<br>
<br>
*)When for Silicon: Minimum grid value :0.001411 and <br>
Maximum grid value : 0.87371<br>
What should be the ideal isovalue? Are there any rules to select the
isovalues, from the values in *.xsf file? <br>
<br>
(For isovalue of 0.001411(min) & 0.87371(max), no charge density
has been found. )<br>
<br>
Thank you in advance!!!<br>
<br>
Regards<br>
Amit N. Harode<br>
CRL INDIA<br>
<br>
P.S.<br>
Input file for QE's pp.x is as follows, &inputpp<br>
prefix = 'si'<br>
filplot = 'sicharge'<br>
plot_num= 0<br>
/<br>
&plot<br>
nfile = 1<br>
filepp(1) = 'sicharge'<br>
weight(1) = 1.0<br>
iflag = 3<br>
output_format = 5<br>
fileout = 'si.rho.xsf'<br>
/<br>
<br>
<table
style="font-family: Verdana; font-size: 11px; line-height: 15px;"
border="0" cellpadding="0" cellspacing="0" height="57" width="644">
<tbody>
<tr>
<td><a moz-do-not-send="true"
href="http://sigads.rediff.com/RealMedia/ads/click_nx.ads/www.rediffmail.com/signatureline.htm@Middle?"
target="_blank"><img moz-do-not-send="true"
src="http://sigads.rediff.com/RealMedia/ads/adstream_nx.ads/www.rediffmail.com/signatureline.htm@Middle"></a></td>
</tr>
</tbody>
</table>
<pre wrap="">
<hr size="4" width="90%">
_______________________________________________
XCrySDen mailing list
<a class="moz-txt-link-abbreviated" href="mailto:XCrySDen@democritos.it">XCrySDen@democritos.it</a>
<a class="moz-txt-link-freetext" href="http://www.democritos.it/mailman/listinfo/xcrysden">http://www.democritos.it/mailman/listinfo/xcrysden</a>
</pre>
</blockquote>
</body>
</html>