water on graphene

Dear all,

I am trying to calculate the contact angle of a water droplet (SPC/E)
on graphene (AIREBO). I can easily model the water droplet and only
the graphene sheets, but when I try to combine the two I don’t know
what LJ coefficients to add for the interaction water/graphene.
I have had a look at some papers but the MD run is still not very stable.
The sheets move apart way too much.

I am trying to do REBO for carbon and add the LJ for ‘C-O’:
Could someone please advice on what parameters to add for the LJ
interaction or how to get around this problem?.

Regards,
Adriano

------- input file ------

read_data data.graphene5_CA
pair_style hybrid rebo lj/cut/coul/long 14.0
pair_coeff * * rebo CH.airebo C NULL NULL

pair_coeff 1 2 lj/cut/coul/long 0.0 0.0 #C-H
pair_coeff 1 3 lj/cut/coul/long 3.2779 0.1037 # C-O

pair_coeff 2 3 lj/cut/coul/long 0.0 0.0 #H-O
pair_coeff 2 2 lj/cut/coul/long 0.0 0.0 #H-H
pair_coeff 3 3 lj/cut/coul/long 0.1555 3.166 #O-O

You could look in the literature for water on graphene models.

which would presumably have similar params for the water/C interactions.

Steve