priyanka srivastava wrote:

I have used PME and have mentioned rcoulomb in the
.mdp file too, which as is pointed out by you, has no
meaning!! But does this mean that my mdp file is
wrong? Because if PME does not use rcoulomb it shud
simply ignore the value.

As you'd see by reading sections 4.9 and 7.3.9 of the manual, Martin's statement isn't right. The grid dimensions are controlled by the two parameters he mentioned, but there are plenty of other parameters that influence PME.

You're right, in that if mdp file parameters will be ignored then the value you use isn't relevant.

Actually I do not want to use twin range cutoff. So, I
have given rvdw = rlist. Is this alright?

Yes, see section 4.6.3. This is only relevant for vdw since coulombtype = PME

Portion of my mdp file looks like this:

; Electrostatics
coulombtype             =  PME
fourier_nx              =  6.4
fourier_ny              =  5.0
fourier_nz              =  8.1
pme_order               =  4
rcoulomb                =  1.5
rvdw                    =  1.5

Assuming you got these values from somewhere sensible and that they're consistent with the force field you're using, then this will give you some numbers that have at least as good a chance of corresponding to reality as anything :-)

Also since I have not specified "vdwtype" in the mdp
file, so it automatically takes Cut-off.

Set it specifically, so that you don't have to remember what the default is in a year's time.

Mark
_______________________________________________
gmx-users mailing list    gmx-users@gromacs.org
http://www.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at http://www.gromacs.org/search before posting!
Please don't post (un)subscribe requests to the list. Use the www interface or send it to [EMAIL PROTECTED]
Can't post? Read http://www.gromacs.org/mailing_lists/users.php

Reply via email to