[gmx-users] About Simulated Annealing

[Weihua Li]

Hi all,
  I want to perform a MD with simulated annealing.But i don't know how to use the parameters in .mdp file(e.g. cooling down from 500k to 100k).It seems to only have a parameter that cooled down to 0K,Zero_temp_time. How to control the system to cool down to 100K?
 Could anyone give me some suggestions? Thank you very much!
 Below is my .mdp file:

title               = Yo
cpp                 = /lib/cpp
define              = -DFLEX_SPC   
constraints         = all-bonds
integrator          = md
dt                  = 0.002 ; ps !
nsteps              = 1000000 ; total 100 ps.
nstcomm             = 1
comm_grps           = Protein 
nstxout             = 500
nstvout             = 1000
nstfout             = 500
nstlog              = 500
nstenergy           = 500
nstlist             = 10
ns_type             = grid
coulombtype         = PME
rlist               = 0.9
rcoulomb            = 0.9
rvdw                = 0.9
fourierspacing      = 0.12
pme_order           = 4
optimize_fft        = yes
; Berendsen temperature coupling is on in two groups
Tcoupl              = berendsen
tc-grps             = Protein  SOL 
tau_t               = 0.1      0.1 
ref_t               = 500      500 
; Energy monitoring
energygrps          = Protein SOL 
; Pressure coupling is on
pcoupl              = berendsen
pcoupltype          = isotropic
tau_p               = 1
compressibility     = 4.5e-5
ref_p               = 1.0
; Generate velocites is on at 500 K.
gen_vel             = no
gen_temp            = 500.0
gen_seed            = 173529
;simulated annealing
annealing           = yes
zero_temp_time      = 1400



Cheers,
Roy