Thanks Chris and Mark!<br><br>2008/4/21 Chris Neale <<a href="mailto:chris.neale@utoronto.ca">chris.neale@utoronto.ca</a>>:<br><blockquote style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;" class="gmail_quote">
I
use tip4p/opls/berger combination and it works well for me. I have
never used tip5p. I suggest that you build your membrane and run one
control simulation (sounds like you would lean toward using spc for
this) and then one simulation with tip5p. Check order parameters and<br>
area per lipid while using anisotropic pressure coupling.<br></blockquote><div><br>Surely I'll try to see for myself how bad different water models perform :) Still, I was hoping that I could get some info beforehand (like if someone told me that TIP5P absolutely screws up the results for Berger; such kind of advice can really save one time).<br>
<br></div><blockquote style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;" class="gmail_quote">
Also, are you sure that you want to use tip5p? <br><br>
Chris.</blockquote><div><br>I'm afraid I have to use TIP5P; I _am_ looking at temperature dependent information, and also, I need a good description of hydration of small molecules I mentioned. These and other considerations make more or less every other water model I know of (including TIPxP-Ew) at least twice less attractive than TIP5P. So if TIP5P doesn't screw up the description of the membrane as much as any other model would the water part, I think it will do.<br>
</div>
<br><div class="gmail_quote">2008/4/22 Marc F. Lensink <<a href="mailto:lensink@scmbb.ulb.ac.be">lensink@scmbb.ulb.ac.be</a>>:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div class="Ih2E3d"><br>
</div>i'm very happily using berger/oplsaa/tip4p. mind that this means ua<br>
lipid tails and the rest aa, so unless you have a distinct lipid<br>
phase, it's probably not what you want. personally i'm not (yet)<br>
convinced it's a better combination than berger/gromos/spc, though.<br>
<br>
cheers,<br>
marc<br>
</blockquote></div><br>I'm sorry, I didn't quite understand the argument about 'having a distinct phase'. Could you please elaborate?<br><br>So, this leaves us with two votes for Berger/TIP4P and nothing at all about CHARMM27. But it would be really nice to hear from someone who'd been using the latter FF. (I realize that it might be smarter to ask such questions on the CHARMM forum, but on the other hand, I'm still willing to do this in GROMACS...)<br>
<br>Thanks again,<br>Vasilii<br>