dipole for united atom with OOPSE

[Dan Gezelter]

Dr. Feng,

That is a very good question.  In the version of OOPSE currently
available for download, the only way to set the moment of inertia
tensor is in the actual code (in libmdtools/DUFF.cpp).  Look for
lines that set headI or waterI for an example.  The HEAD atoms
have the Z-axis pointing along the dipole moment.

We are currently working on an updated version of OOPSE which (among
other improvements) will allow you to specify other moments of
inertia in the force field file itself, but an unfortunate early
design decision was to hard-wire the moments of inertia in the code.

The easiest way to do what you want with the current code
is to override the HEAD atom properties in that code and
recompile.

Let me know how it goes!

  --Dan Gezelter

Xiaobing Feng wrote:
> Dear Dr. J. Daniel Gezelter,
>        Sorry to trouble you.
>        I'm a postdoc at Chemistry depearment of the University of 
> Chemistry.
> Now we are going to study a simple system, i.e., monoatomic (united atoms)
> molecules with dipoles.
>        OOPSE can assign a dipole to an united atom (the head of lipid). 
> I tried
> to remove all the waters and other atoms from liquid, keeping only the 
> heads,
> so we got a collections of pseudoatoms with dipoles. I just don't know 
> how to
> specify the moment of inertia to united atoms. I couldn't find them in 
> DUFF.frc
> and 5x5.in.  Could you please tell me how to do that?
>        I'll appreciate your reply very much. Sorry for the trouble, and 
> thank you
> very much.
>        Yours,
>                Xiaobing Feng
> 
> 
> ------------------------------------------------
> Xiaobing Feng
> Chemistry Department
> University of Kansas
> Phone: 785-864-4158