$ cat ~/emamber.mdp
define                   = -DFLEXIBLE
integrator               = cg ; steep
nsteps                   = 1000
constraints              = none
emtol                    = 1000.0
nstcgsteep               = 10 ; do a steep every 10 steps of cg
emstep                   = 0.01 ; used with steep
nstcomm                  = 1
coulombtype              = PME
ns_type                  = grid
rlist                    = 1.0
rcoulomb                 = 1.0
rvdw                     = 1.4
Tcoupl                   = no
Pcoupl                   = no
gen_vel                  = no
nstxout                  = 0 ; write coords every # step
optimize_fft             = yes