[gmx-users] my octane was divided into four parts

[nanyu101]

Dear gmx-users,
  Before i ask my question, I should thanks Dr.Tieleman firstly.My octane slab was sent by Dr.Tieleman.
  My gro file was sent by Dr.Tieleman. But I failed in minimizing the octane slab normally.I have minimized it withou water firstly, and then I add water in the z direction. When i continued to minimized the water+octane,my octane was divide into four separate parts.Why?
my em.mdp
title               =  try toxin
cpp                 =  /lib/cpp
define              =  -DFLEX_SPC
constraints         =  none
integrator          =  cg
ntcgsteep           =  50
dt                  =  0.002
nsteps              =  20000
nslist              =  5
ns_type             =  grid
pbc                 =  xyz
rlist               =  0.9
coulombtype         =  pme
rcoulomb            =  0.9
rvdw                =  1.2
fourierspacing      =  0.12
fourier_x           =  0
fourier_y           =  0
fourier_z           =  0
pme_order           =  4
ewald_rtol          =  1e-5
optimize_fft        =  yes
emtol               =  500
emstep              =  0.01
Tcoupl              =  berendsen
tau_t               =  0.1 0.1
tc-grps             =  OCT SOL
ref_t               =  300 300
pcoupl              =  berendsen
Pcoupltype          =  anisotropic
tau_p               =  1.0 1.0 1.0 0 0 0
compressibility     =  4.5e-5 4.5e-5 4.5e-5 0 0 0
ref_p               =  1.0 1.0 1.0 0 0 0
gen_vel             =  yes
gen_temp            =  300
gen_seed            =  11

I do not know what the wrong is.Thanks for advance!!
Best wishes,
nanyu
______________________________________
Best wishes,
nanyu
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