sample from NVT
 &cntrl
  ipimd = 2
  ntb = 1,cut = 7.0,
  temp0  = 298.15, tempi = 298.15,
  ntt = 4, nchain = 4,
  dt = 0.0001, nstlim = 10000,
  nscm = 1000,
  ntx = 5, irest = 1,
  ntwx = 10,     
  ntwr = 10,       
  ntpr = 10,         
 /
 &ewald
  skinnb = 2.0
 /