[gmx-users] temperature too high with reaction field

[sam.moors at chem.kuleuven.be]

Hi gmx users,

I'm trying to simulate a water box filled with TIP3P water.
With PME, everything seems OK.
However, when I switch to reaction field electrostatics,
the temperature in the output files is too high: 
312K instead of 300K (the t_ref value for the whole system).
Maybe there is something wrong with my input paramters?
Below you find my .mdp file

Thanks,
Sam

integrator  = md
dt   = 0.002 ; ps !
nsteps   = 20000
nstcomm  = 1
nstxout  = 500
nstvout  = 0
nstlog  = 500
nstenergy = 500
nstfout  = 0
nstlist  = 10
ns_type  = grid
rlist   = 1.2
coulombtype  = Reaction-Field 
epsilon_r = 1
epsilon_rf = 78
rcoulomb  = 1.2
table-extension = 1
vdwtype  = cutoff
rvdw   = 1.2
fourierspacing  = 0.19
fourier_nx  = 0
fourier_ny  = 0
fourier_nz  = 0
pme_order  = 4
ewald_rtol  = 1e-5
optimize_fft  = yes
; temperature coupling
Tcoupl   = v-rescale
tau_t   = 1.0
tcgrps   = system
ref_t   = 300
; Pressure coupling
Pcoupl = parrinello-rahman
tau_p = 1.0
compressibility = 4.5e-5
ref_p = 1.0
; Generate velocites
gen_vel  = no
gen_temp  = 300
gen_seed = 173529


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