On 31/10/2010 10:04 AM, chris.ne...@utoronto.ca wrote:
Justin is probably correct, your system is unstable. However, let me mention another possibility. As the temperature increases, the largest stable timestep decreases in length. Is it possible that over some temperature (>1000K?) a 2 fs timestep is no longer viable? In this case, even a well minimized system with a large number for lincs_iter is still going to give you incorrect sampling and possibly crash. You'd need to reduce you highest temperature or reduce your timestep.

I don't know if the gromacs REMD algorithm allows you to use a smaller timestep at higher temperatures, but it's something to look into.
It doesn't. Off the cuff, I can't say whether it's sound to simulate at a smaller timestep at higher temperature and exchange with a simulation that has done the same number of larger timesteps.

Mark

Chris.

-- original message --

For Replica exchange, is there any advantage of in using SHAKE over
LINCS(other than the stepsize)?
I am running an REM simulation and the simulation stops after running for
variable number of steps (100000, 10000000 etc.) because some bond moves
more than 30 degrees and LINCS gives a warning.


Pooja



--
gmx-users mailing list    gmx-users@gromacs.org
http://lists.gromacs.org/mailman/listinfo/gmx-users
Please search the archive at 
http://www.gromacs.org/Support/Mailing_Lists/Search before posting!
Please don't post (un)subscribe requests to the list. Use the www interface or send it to gmx-users-requ...@gromacs.org.
Can't post? Read http://www.gromacs.org/Support/Mailing_Lists

Reply via email to