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Dear GMX-users.<br>
<br>
I'm trying to do free energy calculations for calculations of
partitions coefficients.<br>
<br>
My normal defaults section of TraPPE topologies are:<br>
<br>
<b>; nbfunc comb-rule gen-pairs fudgeLJ fudgeQQ<br>
1 3 no
0.5 0.5<br>
</b><br>
because TraPPE don't use 1-4 LJ interaction, and I have read that
FudgeQQ always apply even though gen-pairs=no.<br>
<br>
Now I want to do my calculations with OPLS-AA for the solute molecule,
and TraPPE-UA for the solvent, so my default section must now be:<br>
<br>
<b>; nbfunc comb-rule gen-pairs fudgeLJ fudgeQQ<br>
1 2 yes
0.5 0.5<br>
</b><br>
, but the problem arises when I have for instance Ethanol in my
solvent, then gen-pair will calculate LJ 1-4 interactions for the
Ethanol as well.<br>
<br>
But if I in the .top for the ethanol pair write:<br>
<br>
<b>[ pairs ]<br>
; ai aj funct c6 c12<br>
1 4 1 0.000000e+00 0.000000e+00;<br>
</b><br>
then will the 1-4 LJ be 0, but the 1-4 Coulomb will still be calculated
- right??<br>
<br>
Also, can I check all the interaction parameters calculated and
inserted by grompp?<br>
<br>
Best regards.<br>
Rasmus Lundsgaard<br>
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