HYDRATED_ION_WATER potential

[haoyuan]

Hi David and All,

I'm trying to use the HYDRATED_ION_WATER potential for certain atom pairs in a MC simulation. According to the RASPA manual (Page 82), it takes 5 arguments. I defined a force_field.def file like this:

# rules to overwrite
0
# number of defined interactions
1
# type      type2       interaction
Mg_         Ow          hydrated_ion_water     0.0    0.0    135125.0    61969.0    -32557086.0
# mixing rules to overwrite
0

However, when I started the simulation, I found from the output file that the last two parameters in the potential were also zero although I assigned them non-zero values:

Ow -     Mg0 [HYDRATED_ION_WATER_SMOOTHED5] p_0/k_B:  0.00000 [K], p_1:  0.00000 [A^-1], p_2/k_B: 135125.00000 [K A^4], p_3/k_B:  0.00000 [K A^6], p_4/k_B:  0.00000 [K A^12]

How can I make p3 and p4 to be the values I assigned? Thank you!

Haoyuan

[David Dubbeldam]

You do a: grep HYDRATED_ION_WATER *.c
in the source code and get the files back where this is used.
In the file 'potentials.c' you can check whether it is read okay, or printed out wrongly, or whether it is something with the mixing rule.