How to use diffuse reflective boundary condition in lammps

I am studying the heterogeneous nucleation on surface and I want to use the diffuse reflective boundary condition for one face of box ! And I search the description about the diffuse reflective in the manual and I do not find useful information. So I want to know lammps can use diffuse reflective boundary or not. And Which commands should I see to realize the diffuse reflective boundary condition ? Thank you for your help!

I am studying the heterogeneous nucleation on surface and I want to use the
diffuse reflective boundary condition for one face of box ! And I search
the description about the diffuse reflective in the manual and I do not find
useful information. So I want to know lammps can use diffuse reflective
boundary or not. And Which commands should I see to realize the diffuse
reflective boundary condition ? Thank you for your help!

you *still* haven't explained, what a "diffuse reflective boundary
condition" is and what its purpose is.

axel.

1 Like

I am familiar with the concept of diffuse reflection. Essentially, instead of specular reflection, where the normal component of the velocity is reversed and the lateral component is conserved, which is what fix wall/reflect does, in diffuse reflection, the reflected velocity is randomly sampled from a distribution function, which is based on a physical model of scattering from the surface. If the distribution function has a simple mathematical form (does it depend on incident velocity or temperature?), it would not be hard to add it as an option to fix wall/reflect.

I will also mention that you could probably achieve a similar result by applying a very strong Langevin thermostat in a narrow region near the wall.

Aidan