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<span style="color: rgb(0, 0, 0); font-family: 'Times New Roman';
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255); font-size: medium; display: inline ! important; float:
none;">Hi </span>Andrew,<br>
at <a href="http://manual.gromacs.org/online/mdp_opt.html#nl">http://manual.gromacs.org/online/mdp_opt.html#nl</a>
the manual says:<br>
<span style="color: rgb(0, 0, 0); font-family: 'Times New Roman';
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-webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px;
background-color: rgb(255, 255, 255); font-size: medium; display:
inline !important; float: none; ">"Without walls or with only one
wall the system size is infinite in the z direction. Therefore
pressure coupling or Ewald summation methods can not be used.
These disadvantages do not apply when two walls are used"<br>
<br>
So I guess wall are physical walls, i.e. something limitating the
expansion of your system in the z-direction. In the xy plane the
system is replicated because of pbc but,<br>
without walls, it would be unlimited in the z-direction.<br>
<br>
<br>
<br>
<br>
</span>Il 10/03/2012 17:46, Andrew DeYoung ha scritto:
<blockquote cite="mid:654E40408F4949A8B385536544FAFF1C@DELLXPS410"
type="cite">
<pre wrap="">Hi,
Only if you have time, do you know of any resources that explain the concept
of a Gromacs wall, which seems related to 2-D Ewald summation? In the
Gromacs 4.5.4 manual, the parameters related to walls are described on page
182, and also on <a class="moz-txt-link-freetext" href="http://manual.gromacs.org/current/online/mdp_opt.html#walls">http://manual.gromacs.org/current/online/mdp_opt.html#walls</a>
. But do you know of any general explanations, books, or literature papers
that would help me to understand what a wall does and why and when I need to
use them? I cannot seem to find them discussed in the main Gromacs papers (
<a class="moz-txt-link-freetext" href="http://www.gromacs.org/Documentation/Gromacs_papers">http://www.gromacs.org/Documentation/Gromacs_papers</a> ).
Also, is there another name for a simulation wall? When I use Google to
search for "MD simulation wall", it is not clear that I am looking for the
correct thing.
Thanks so much for your time.
Andrew DeYoung
Carnegie Mellon University
</pre>
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