[gmx-users] Melting temperature for the lipid bilayer

[Mohsen Ramezanpour]

Dear gromacs users,

Running simulation on a lipid bilayer made by Charmm-GUI, there is about 24
degrees difference between the reported temperature in Avanti and what I
see in my simulations for getting a liquid disordered (L_disorder) bilayer.

I am using all-atom Charmm36 FF for simulations.
I know that it is not possible to get an exact match between experimental
and simulation T values for L_alpha phase of bilayers, but I am not sure if
these gap seems reasonable or there is something wrong in my simulations. I
have checked the bonds in tails and apparently, everything looks fine with
topology.

However, based on this, doing simulation in L_alpha phase requires hight T
values (close to 85 or 90 degrees of centigrade) which makes me worry about
the water molecules in the system. It is a high temperature for water
molecules.

Its worth mentioning that bilayer structural properties like lipid order
parameters match available experimental data for these high T values.

Please let me know your opinion.

Cheers
Mohsen

-- 
*Rewards work better than punishment ...*