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<a class="moz-txt-link-abbreviated" href="mailto:spoel@xray.bmc.uu.se">spoel@xray.bmc.uu.se</a> wrote:<br>
<blockquote type="cite" cite="mid1096729722.9320.33.camel@h32n2fls34o1123.telia.com">
<pre wrap="">On Sat, 2004-10-02 at 16:48, Hector Mrz-Seara Monne wrote:
</pre>
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<blockquote type="cite">
<blockquote type="cite">
<pre wrap="">
</pre>
</blockquote>
<pre wrap="">OK that looks fine. Have you verified (md.log file) that these settings
have been incorporated in the tpr file?
</pre>
</blockquote>
<pre wrap="">It seems that every thing is ok
</pre>
<blockquote type="cite">
<pre wrap="">Have you tried visualising the trajectory?
</pre>
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<pre wrap="">Every thing seems normal if you make a overall view. But after
checking one by one all the monomers one of them seem to kill
itself.The main part of the sistem is very rigid with many impropials
defined along it, benzene-N=N-benzene ( it must be all in a plane). I
notice when I was trying to parametrice the molecule that if I try to
keep it complete plane whit impropial then the structure crash in a
dyanmic, It seems like the molecule enter in a kind of resonance
effect that finish with unnatural bond legth and angles and the
crashing of the system. I pass through this problem changing some
impropials for propials with a loose in the planarity. It seems that
this fenomenom is crashing my system again. Have you any suggestion?
Thank you.
</pre>
</blockquote>
<pre wrap=""><!---->
Try equilibrating at lower temperature and/or with a shorter time step.
In particular since you describe this resonance thing. Could it be that
your force constants are too high? You should have roughly 20 time steps
in a complete period of the fastest motion.
</pre>
</blockquote>
Thanks in advance for all your help, it's been quite useful for me in order
to increase my knowledge on this suite.<br>
I've been thinking in the last suggestion and I'm not sure about the meaning.
As I understand if I use high constants <br>
for defining my proper dihedrals I have to reduce my time steep that actually
is quite small 1fs only or work at lower temperature.<br>
Here the *.itp file of the monomer contain this lines that I have specifically
modify to have a planarity system.<br>
<br>
.....<br>
[ dihedrals ]<br>
;ai aj ak al fu c0 c1 m c0 c1 m<br>
9 12 10 8 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CBA CAD CAE
CAU<br>
14 15 13 11 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CBB NAV CAF
CAG<br>
17 16 20 18 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CBC NAW CAH
CAI<br>
22 23 21 19 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CBD OAY CAJ
CAK<br>
27 26 29 28 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CAZ CAT OAX
OAC<br>
17 18 19 22 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CBC CAI CAK
CBD<br>
18 19 22 21 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CAI CAK CBD
CAJ<br>
19 22 21 20 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CAK CBD CAJ
CAH<br>
22 21 20 17 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CBD CAJ CAH
CBC<br>
21 20 17 18 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CAJ CAH CBC
CAI<br>
20 17 18 19 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CAH CBC CAI
CAK<br>
9 10 11 14 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CBA CAE CAG
CBB<br>
10 11 14 13 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CAE CAG CBB
CAF<br>
11 14 13 12 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CAG CBB CAF
CAD<br>
14 13 12 9 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CBB CAF CAD
CBA<br>
14 15 17 16 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CBB NAV CBC
NAW<br>
13 12 9 10 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CAF CAD CBA
CAE<br>
12 9 10 11 2 0.0 1673.6 0 0.0 1673.6 0 ; IDI CAD CBA CAE
CAG<br>
4 3 2 1 1 0.0 5.9 3 0.0 5.9 3 ; DI CAN
CAM CAL CAA<br>
.....<br>
11 14 15 16 1 180.0 53.5 2 180.0 33.5 2 ; DI CAG CBB NAV
NAW *<br>
15 16 17 20 1 180.0 53.5 2 180.0 33.5 2 ; DI NAV NAW CBC
CAH *<br>
.....<br>
25 26 27 29 1 0.0 0.4 6 0.0 0.4 6 ; DI CAR CAT
CAZ OAX<br>
26 27 29 30 1 180.0 16.7 2 180.0 16.7 2 ; DI CAT CAZ OAX
HE2 *<br>
<br>
Do you know if your advise works equally for both proper and improper dihedrals?
If not can you tell me the diference?<br>
I think for your coment that the dihedral with the asterisk that are the
problematic? witch time step will you use, or do you know any <br>
way to avoid the restriction that my system contain?<br>
<br>
Thank you very much for taking your time to answer me, David. If you think
you need any other information or that is not clear what<br>
I'm asking for just tell me and I can send you any indormation or foles
that you thing could be usefull to solve my actual problems<br>
<br>
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