Please read about obtaining diffusion constant from VAC in the gromacs wiki. I wrote an individual article on that topic.<br><br> Best,<br> Vitaly<br><br><br><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Subject: RE: [gmx-users] transport properties<br>
To: Discussion list for GROMACS users <<a href="mailto:gmx-users@gromacs.org">gmx-users@gromacs.org</a>><br>
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Dear K. Chae,<br>
<br>
Thank you very much for your answer. I computed velocity auto-correlation (VAC) functions , but how can I integrate velocity auto-correlation (VAC) functions to get Diffusion coefficient using xmgrace software ? I have just used xmgrace to plot md result for analysis. And I have a limited information using xmgrace. Could you please explain the integration procedure in xmgrace ? I will be very grateful if you can help me to learn how to calculate Diffusion coefficient .<br>
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Thanks in advance for your helps.<br>
<br>
Best regards,<br>
<br>
--- On Tue, 4/28/09, kyungchan chae <<a href="mailto:ckcumaa@umich.edu">ckcumaa@umich.edu</a>> wrote:<br>
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<br>
From: kyungchan chae <<a href="mailto:ckcumaa@umich.edu">ckcumaa@umich.edu</a>><br>
Subject: RE: [gmx-users] transport properties<br>
To: "'Discussion list for GROMACS users'" <<a href="mailto:gmx-users@gromacs.org">gmx-users@gromacs.org</a>><br>
Date: Tuesday, April 28, 2009, 9:52 AM<br>
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Once you have correlation results then xmgrace software can do the integration.<br>
<br>
Regards<br>
<br>
<br>
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Dear All,<br>
I'm trying to calculate self diffusion coefficient from velocity auto-correlation (VAC) functions using Green-Kubo relation in figure I attached to the mail. I couldn’t solve how to integrate the velocity auto-correlation (VAC) functions to get Diffusion coefficient. Could you please give me some information about this issue ? Could you suggest some software to integrate the VAC function ?<br>
Thanks in advance for your helps.<br>
Best regards,<br>
<br>
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