CHARMM Improper coefficient for Graphene

Hi
I want to simulate Graphene Oxide with CHARMM force field. I used all parameters from ( par_all27_prot_lipid.inp ) file . But i dosen’t have improper coefficient for carbon’s in graphene. Now I want to know that is it necessery to define improper for Graphene?
If yes, Is there an article in which it has been calculated?

Best Regards

Isaac

‪On Tue, Jan 29, 2019 at 10:38 AM ‫اسحاق خداپرست سیاهمزگی‬‎
<[email protected]...> wrote:‬

Hi
I want to simulate Graphene Oxide with CHARMM force field. I used all parameters from ( par_all27_prot_lipid.inp ) file . But i dosen't have improper coefficient for carbon's in graphene. Now I want to know that is it necessery to define improper for Graphene?

i don't think so. but don't take my word for it.

If yes, Is there an article in which it has been calculated?

in general, to find this kind of information, you have to search the
published literature. that is where you'll find definite answers. all
CHARMM parameter sets are properly documented and their
parameterization described in the corresponding articles. Alex
MacKerell's homepage has not only links to the official CHARMM force
field archives, but should also list (most) relevant publications.

axel.

Hi Dr. Axel

Thanks for your guide.
I will visit Alex MacKerell’s Homepage.

Best Regards.
Isaac