Re: [AMBER] Confusion in urea Model

From: David A Case <>
Date: Wed, 15 Nov 2017 07:26:15 -0500

On Wed, Nov 15, 2017, Saikat Pal wrote:

> Dear Amber community,I want to work using Deep Eutectic Solvent Choline
> chloride and Urea (1:2) mixture.So for this work, I want to take
> Gaff-forcefield. For urea, I have followed geometry optimization then
> antechamber.From antechamber, I have got prepc and frcmod file.But In
> amber manual 2015 page no -47, there is also file present as frcmod.urea
> in solvents models.My Question is to do this DES work for urea, Should
> I load All three file : .prepc, .frcmod (both from antechamber) and
> frcmod.urea (from solvents.lib)?Please Help me out.

I would recommend sticking with gaff, and ignoring the frcmod.urea file. That
way, you have a consistent approach. Note that it may still not be accurate
enough to provide accurate thermoynamics for a fluid mixture, and you should
consult the literature to see what force fields others have used (and perhaps
optimized) for urea-based solvents.

Also: be sure to use gaff2 and parmchk2: these are likely to be better suited
for liquid properties than the gaff version 1.x (no guarantees, however.)

...good luck....dac

AMBER mailing list
Received on Wed Nov 15 2017 - 04:30:03 PST
Custom Search