[gmx-users] Mailing list and multiplicity

[Mark Abraham]

Peyman Yamin wrote:
> Dear GMXers,
> 
> Is there still any way to search the mailing list archive in the new
> hypnotizing web site?

Justin posts it about once a week, but just googling 
"site:lists.gromacs.org multiplicity zero" does the job.

> Another question I would have first looked up in the mailing list, if
> I could, is if gromacs can account for torsions with a zero
> multiplicity. In the end it's just a constant in the formula and may
> sometimes need to be set to zero (say Kukol and Martinez-Seara). I'm
> trying to use Kukol Lipids but get a Fatal Error :-S
> Value of 'multiplicity' in Proper Dih. is 0, which is smaller than the
> minimum of 1
> 
> This seems to be caused by some lines in the lipid's .itp file of
> popc, which read something like this:
> 
> [ dihedrals ]
> ;  ai    aj    ak    al funct   phi0     cp     mult
> ..
> ..
>   22    23    24    25     1    90    -5.685     0
> ..
> ..

As some of those links will point out, since MD does not use the energy 
for the integration of the forces, then under at least some 
circumstances you should be commenting such lines out in order to move 
forward.

Mark