;
; "Nico ions": NaCl from (1) with scaling parameter for Na-O(H2O) from (2)
;
; (1) Weerasinghe S, Smith PE (2003) A kirkwood-buff derived force field for
; sodium chloride in water. J Chem Phys 119:11342–11349.
; (2) Berk Hess and Nico F. A. van der Vegt (2009) Cation specific binding
; with protein surface charges. PNAS 106:13296-13300
;
; For use with OPLS
;

[ moleculetype ]
; molname   nrexcl
NA          1

[ atoms ]
; id    at type     res nr  residu name at name  cg nr  charge   mass
1       nico_na     1       NA          NA       1      1        22.98977     

[ moleculetype ]
; molname   nrexcl
CL      1

[ atoms ]
; id    at type     res nr  residu name at name  cg nr  charge   mass
1       nico_cl     1       CL          CL       1      -1       35.45300

[ atomtypes ]
; name  bond_type    mass    charge   ptype          sigma      epsilon
 nico_cl    Cl-  17  35.45300    -1.000       A    4.40E-001    4.70E-001
 nico_na    Na+  11  22.98977     1.000       A    2.45E-001    3.20E-001

[ nonbond_params ]                      
; i       j        func    sigma(ij)       epsilon(ij)
  nico_na opls_111 1       0.2778          0.3385         ; this scales Na+ to O(tip3p) epsilon by 0.75