dmllt1 RNA with counter ions: initial minimization solvent _ ions
 &cntrl
  imin = 1,
  maxcyc = 1000,
  ncyc = 500,
  ntb = 1,
  ntr = 1, 
  cut = 10.0
  /
Hold the RNA fixed
500.0
RES 1 137
END
END