Hi Community:

I am studying the changing the parameters of force field for three site nitrogen.(H in the middle)
I saw one of post about changing the parameters.

https://r1132100503382-eu1-3dswym.3dexperience.3ds.com/#community:PicGX_96TjmPwe9tdYLC4w/iquestion:lkHSmSxOTz-IB7XMlFNRng

Which Someone suggested on changing the bond and angle interactions.
I used the Trappe force field on "Types" section (LJ 12_6). and follow the instructions on the post.

van der Waals
H___b IGNORE 0.1000000000000000

Bond Stretch
N_3 H___b IGNORE

Angles
X H___b X IGNORE

I tried to run a NVT dynamic test to see whether the gas is stable,(no cell)
but seems like the three site nitrogen isn't linear and the bond lengths are incorrect.
It ended up with something like the image below
I also tried to set the van der waals in the interaction section to make the N atoms ignore each other.
but the results still ended up with 3.6 Amstrong bond length between N atoms.
Plus the temperature in NVT results are not stable (9.64K in the end of the run)
Did I still miss any parameters?
or is it normal for Nitrogens to act this way?
Thank You very much!!