[gmx-users] Simulated Annealing problem

[mon_sharma at research.iiit.ac.in]

Dear All,
I am trying to do simulated annealing for solvated protein system.
the excerpts of the file is as:

energygrps               = protein non-protein
;Temperature coupling
tcoupl                   = Berendsen
tc-grps                  = protein non-protein
tau_t                    = 0.1 0.1
ref_t                    = 300 300
;Pressure coupling
Pcoupl                   = berendsen
Pcoupltype               = isotropic
tau_p                    = 1.0
compressibility          = 4.5e-5
ref_p                    = 1.0
;Velocity generation
gen_vel                  = yes
gen_temp                 = 300
gen_seed                 = 173529
; SIMULATED ANNEALING
; Type of annealing for each temperature group (no/single/periodic)
annealing                = single single
; Number of time points to use for specifying annealing in each group
annealing_npoints        = 7 7
; List of times at the annealing points for each group
annealing_time           = 0 250 250 250 250 500 500 1000 0 250 250 250 
250 500 1000
; Temp. at each annealing point, for each group.
annealing_temp           = 300 330 360 345 330 315 300 300 330 360 345 330 
315 300

The log however shows that the ref_t increase from 300K to 330K in 250ps 
and then it decreases to 300K in 750ps, and the temperature is aftwerwards 
maintained at 300K. From the input, it should increase to 360K and then 
decrease to 345,330,315 and 300K. But this is not happening.
To check whether its because of temperature couple, t_coupling was 
removed. But then during .tpr formation, it complained of providing two 
groups.  Will then SA wont take two groups (protein and non-protein)?
Why is it so then the temperature rises till 330 only, not after that, and 
it comes down?

All suggestions are welcome.

Thanking in advance,
Regards,
Monika