<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" 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 14 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:11.0pt;
font-family:"Calibri","sans-serif";}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{mso-style-priority:99;
color:purple;
text-decoration:underline;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri","sans-serif";
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri","sans-serif";}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>To All,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I think I know the answer to this question, but I’d like an expert opinion, nonetheless.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>What are the units of “isosurface” plotted by XCrySDen using output from pp.x passed through a .xsf file? I suspect it’s something like<o:p></o:p></p><p class=MsoNormal>normalized total cell charge (i.e., “e=1 times the number of filled non-core pseudo-orbitals per unit cell) divided by a.u.^2. Suppose I have a structure I’m examining with XCrySDen with max/min values, let’s say (+3,-1), and I select +0.25. What exactly is this number in “The Creator’s Units,” sometimes known as SI. I’ve poured through the source code of chdens.f, but get lost trying to guess the pneumonic of each variable.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Seriously, I’m writing up a paper comparing the distribution of charge in various (n,m) carbon nanotubes, and want to avoid dumb errors.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Paul Grant<o:p></o:p></p><p class=MsoNormal>W2AGZ Technologies<o:p></o:p></p><p class=MsoNormal>Associate Staff, JPL/NASA/CalTech<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>