<html>
<head>
<meta content="text/html; charset=ISO-8859-1"
http-equiv="Content-Type">
</head>
<body bgcolor="#FFFFFF" text="#000000">
On 25/08/2011 12:00 AM, <a class="moz-txt-link-abbreviated" href="mailto:aiswarya.pawar@gmail.com">aiswarya.pawar@gmail.com</a> wrote:
<blockquote
cite="mid:%20%3C1289424227-1314194424-cardhu_decombobulator_blackberry.rim.net-712697107-@b18.c3.bise7.blackberry"
type="cite">
<pre wrap="">Mark,
The residence time equation goes like this-
P(r)= function (N(t) - N(t+r))dt
Where function(x-y) takes the value of 1 when x=y(x not equal to 0 and y not equal to 0) ie the site occupied and when x not equal to y or both x and y =0. N(t) index of water molecule found in the hydration site at time t.</pre>
</blockquote>
<br>
So that's the autocorrelation of the existence function. Now you
need a geometric criterion for existence. Note that g_hbond with
well-constructed groups will calculate the autocorrelation of the
existence function for an H-bond. See g_hbond -h.<br>
<br>
g_dist, some scripting and g_analyse might be necessary for other
criteria.<br>
<br>
Mark<br>
<br>
<blockquote
cite="mid:%20%3C1289424227-1314194424-cardhu_decombobulator_blackberry.rim.net-712697107-@b18.c3.bise7.blackberry"
type="cite">
<pre wrap="">
Aiswarya
------Original Message------
From: Mark Abraham
To: Aiswarya Pawar
Subject: Re: [gmx-users] Hydrogen existence time
Sent: 24 Aug 2011 6:09 PM
On 24/08/2011 10:31 PM, <a class="moz-txt-link-abbreviated" href="mailto:aiswarya.pawar@gmail.com">aiswarya.pawar@gmail.com</a> wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Any idea how can I calculate the residence time of water.
</pre>
</blockquote>
<pre wrap="">
First, seek define what you mean to calculate. If you can't write an
equation down for it, you can't calculate it.
Mark
Sent from my BlackBerry® on Reliance Mobile, India's No. 1 Network. Go for it!</pre>
<br>
<fieldset class="mimeAttachmentHeader"></fieldset>
<br>
</blockquote>
<br>
</body>
</html>