Re: Kb, Ktheta values for TIP3P water model

From: Hadi (
Date: Wed Aug 06 2014 - 15:40:22 CDT

This discussion is in NAMD list and it is about rigid models which use bond
constraints. I do not want to generalize it more than this.

On Wed, Aug 6, 2014 at 1:28 PM, Axel Kohlmeyer <> wrote:

> On Wed, Aug 6, 2014 at 3:41 PM, Hadi <> wrote:
> > In Monte Carlo, you do not need to use a constraint solver to implement
> the
> > rigid models. This is what I like to emphasize: unlike MD, they can
> "easily"
> > be implemented. There is no need to solve a constraint. So I think you
> are
> no. no. no. please pay attention. in MD you can do rigid bodies
> without constraints just as well and instead of solving constraints.
> you just propagate the center of mass and the rotational degrees of
> freedom. this works very well, and i am using it regularly. it just
> isn't implemented in NAMD but it is available in many other MD codes.
> in fact, there are MD codes that *only* support such rigid body
> propagators and do not have a constraint solver at all.
> > mistaken: "the difference you were referring to is the difference
> between a
> > rigid body propagator and using a constraint solver and that has little
> to
> > do with MD vs. MC."
> no. i stand by this sentence. you seem to be forgetting that NAMD is
> not every MD program.
> > I agree the term rigid model used in this thread is the one which uses
> the
> > bond constraints and the discussions pertain to the corresponding
> methods.
> again, you are missing the point i am criticizing. it is not what the
> discussion started with that i have an issue with, but your wholly
> unjustified, unproven, and incorrect generalizations.
> axel.
> > Thanks a lot for your comments.
> > Hadi
> --
> Dr. Axel Kohlmeyer
> College of Science & Technology, Temple University, Philadelphia PA, USA
> International Centre for Theoretical Physics, Trieste. Italy.

This archive was generated by hypermail 2.1.6 : Wed Dec 31 2014 - 23:22:42 CST