[ moleculetype ]
; molname   nrexcl
Na          1

[ atoms ]
; id    at type res nr  residu name at name  cg nr  charge
1       Na      1       Na          Na       1      1

[ moleculetype ]
; molname       nrexcl
K               1

[ atoms ]
; id    at type res nr  residu name     at name  cg nr   charge
1       K       1       K               K        1       1

[ moleculetype ]
; molname   nrexcl
Ca          1

[ atoms ]
; id    at type res nr  residu name at name  cg nr  charge
1       Ca      1       Ca          Ca       1      2

[ moleculetype ]
; molname   nrexcl
Cl          1

[ atoms ]
; id    at type res nr  residu name at name  cg nr  charge
1       Cl      1       Cl          Cl       1      -1
