Re: [ESPResSo-users] multiple potentials on a polymer

[Edward Kim]

Thanks a lot.

By the way,

as I mentioned before, this system is somewhat strange.

I have not had such problems using other mailing list.

When I reply to a question or answer, group email is in "cc" and individual's is in "to".

This is the difference from other mailing lists.

So, I have to "reply to all" or add group email again.

Because I kind of got used to use "reply to" instead of "reply to all", I make a mistake using Espresso mailing list.

I will double-check afterward. 

2011/1/10 Olaf Lenz <address@hidden>

Hi!

Again, please write to the mailing list, not an individual person.

On 01/10/2011 12:06 PM, Edward Kim wrote:
> Thank you very much!!
>
> FENE + harmonic was just an example. I am just trying to produce a
> rigid structure that was implemented with FENE +
> "V(theta)=K(1+cos(theta))". (it looks like bond angle cosine)

This means that besides the bond-length potential, you also want to have
a bond-angle potential. This is a very common case. Note, that a
bond-angle potential is a three-body potential as opposed to a
bond-length two body potential!
To set this up, you will have to use the part command for the various
particles, as you can read in the User's Guide, sec. 5.3.5.

> By the way, In the case of using syntax "polymer", can I just use
> another polymer command with harmonic bond? (please see (1) below) or
> use part command (2)?

You have to use the "part" command. "polymer" will always generate new
particles.

Olaf
--
Dr. rer. nat. Olaf Lenz
Institut für Computerphysik, Pfaffenwaldring 27, D-70569 Stuttgart
Phone: +49-711-685-63607