Re: [AMBER] Simulations without PME

From: David Case <david.case.rutgers.edu>
Date: Tue, 6 Aug 2019 01:18:50 +0000

On Mon, Aug 05, 2019, Tom Kurtzman wrote:

>Is it currently possible to run simulations without using particle mesh
>ewald at all? (using full pairwise calculations of electrostatic
>energies?). With no long range corrections whatsoever?

Are you thinking of a periodic or non-periodic calculation?

For periodic calculations, you can set eedmeth=4: this will compute
pairwise electrostatics out to cut, and nothing beyond that. There will
be no reciprocal calculation done. (See the manual for details.)

However, the maximum value for cut+skinnb is still half the box length.
There is no code in Amber that knows how to compute atom pairs beyond
the minimum-image convention.
>

>The Amber Manual suggests setting the PME cutoff very high.

Can you say exactly where this suggestion is? Sounds nonsensical to me,
unless you are dealing with a non-periodic simulation. But I could be
missing something about why this (seemingly odd) suggestion was made.

....dac

p.s.: just so it is clear to everyone: using eedmeth=4 is *not*
recommended for any type of routine use, and will generally give very
bad results if you just turn that option on.

_______________________________________________
AMBER mailing list
AMBER.ambermd.org
http://lists.ambermd.org/mailman/listinfo/amber
Received on Mon Aug 05 2019 - 18:30:02 PDT
Custom Search