[gmx-users] genion with Na or Ca

[Justin Lemkul]

On 1/12/16 3:19 AM, Turgay Cakmak wrote:
> Hi all,
>
>
> I have a quick question about neutralizing the system. I have a solvated
> system that contains a charged protein of -2q. Is there a major difference
> betwen adding 2 Na ions and a single  Ca ion to neutralize the system
> (using genion)?
>

For the purposes of neutralization, probably not, but note that additive force 
fields do not deal well with divalent ions.  Na+ or K+ are preferable if only 
being used for simple balancing of charge.

-Justin

-- 
==================================================

Justin A. Lemkul, Ph.D.
Ruth L. Kirschstein NRSA Postdoctoral Fellow

Department of Pharmaceutical Sciences
School of Pharmacy
Health Sciences Facility II, Room 629
University of Maryland, Baltimore
20 Penn St.
Baltimore, MD 21201

jalemkul at outerbanks.umaryland.edu | (410) 706-7441
http://mackerell.umaryland.edu/~jalemkul

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