[gmx-users] is there martini CG parameters for K+ ion?

[li he]

Dear gmxers,
I am not sure if I'd better post my question here, but the martini forum
http://www.cgmartini.nl/index.php/forum  does not allow me register and
post my
question there.
I am trying to simulate some KCl solution, but only find martini CG Na+
parameters
at http://cgmartini.nl/images/parameters/ITP/martini_v2.0_ions.itp
I am wondering where I can find martini parameters for K+ ion, or can I
just use martini
Na+ parameters for K+?
If there is a martini parameter of K+, I could image it should be Qd bead
with +1 charge, exactly the same as Na+ parameters at the above link. Yes,
it is upsetting to use the same parameter for Na+ and K+, but we have to
admit the current martini force field is not very fine tuned, thus have to
just use Na+ martini parameters at the above link for K+ if we want to
simulate CG KCl or martini KCl anyway? Can this way be justified if the
simulation results agree with the results of other studies, either
experiments or simulations?
Thanks a lot for your kind help, and any suggestion or comment is very
welcome.
Yours
he li