Hi, The sd integrator is described in the manual as follows: sd An accurate leap-frog stochastic dynamics integrator. Four Gaussian random number are required per integration step per degree of freedom. With constraints, coordinates needs to be constrained twice per integration step. Depending on the computational cost of the force calculation, this can take a significant part of the simulation time. The temperature for one or more groups of atoms (tc_grps) is set with ref_t [K], the inverse friction constant for each group is set with tau_t [ps]. The parameter tcoupl is ignored. The random generator is initialized with ld_seed. When used as a thermostat, an appropriate value for tau_t is 2 ps, since this results in a friction that is lower than the internal friction of water, while it is high enough to remove excess heat (unless cut-off or reaction-field electrostatics is used). NOTE: temperature deviations decay twice as fast as with a Berendsen thermostat with the same tau_t.
It is not clear what is the purpose of this integrator and how is it different from ld. Can someone refer me to a paper? Can such an integrator help in making trajectories less deterministic? Pooja -- Quaerendo Invenietis-Seek and you shall discover. -- gmx-users mailing list [email protected] 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 [email protected]. Can't post? Read http://www.gromacs.org/Support/Mailing_Lists
