Dear all,

To find out the interaction energy (vdwl) in LAMMPS, I created a spherical nanoparticle and a water molecule. What I found out that this energy decreases with increase in distance of water molecule from the nanoparticle which is obvious. But when I am increasing the nanoparticle size the energy varies. I am doing this so that I can compare this Molecular mechanics energy with the obtained energy from quantum mechanics. I did this to avoid using the mixing rule for nanoparticle and water interaction.

Also, is it okay to use any mixing rule even though nanoparticle ( vashsihta potential)uses one potential and water (lj potential)uses some other potential?

Thank You!

Dear all,

To find out the interaction energy (vdwl) in LAMMPS, I created a spherical

nanoparticle and a water molecule. What I found out that this energy

decreases with increase in distance of water molecule from the nanoparticle

which is obvious. But when I am increasing the nanoparticle size the energy

varies. I am doing this so that I can compare this Molecular mechanics

energy with the obtained energy from quantum mechanics. I did this to avoid

using the mixing rule for nanoparticle and water interaction.

you are not making *any* sense here.

Also, is it okay to use any mixing rule even though nanoparticle (

vashsihta potential)uses one potential and water (lj potential)uses some

other potential?

what kind of formula would you apply? how can you mix epsilon and

sigma of a lennard jones potential with a potential that doesn't use

those?

axel.

Dear Sir,

Thank you for the reply.

The question I asked meant that to define the pair coefficient between a nanoparticle and atoms of water, LB mixing rule was used in most of the papers i.e we have a copper nanoparticle with lj parameters and water with lj parameters. But to cross check that I have done quantum mechaincs energy calculation which should match the energy obtained from LAMMPS if the mixing rule approximation is correct. Thank you!

Dear Sir,

Thank you for the reply.

The question I asked meant that to define the pair coefficient between a

nanoparticle and atoms of water, LB mixing rule was used in most of the

papers i.e we have a copper nanoparticle with lj parameters and water with

lj parameters. But to cross check that I have done quantum mechaincs energy

calculation which should match the energy obtained from LAMMPS if the mixing

rule approximation is correct. Thank you!

this is not a LAMMPS question, but a question about validity and

comparability of different methods. this is off-topic for this list

and besides, there is no way to answer this question at this general

level.

axel.