Shape of interface between molecules

Question

Two seas do not mix, what are the characteristics of the interface?

If we are trying to draw the molecules together, what would the interface look like?

Answer 1

Molecules are composed of atoms. Atoms have a nucleus of protons and neutrons and electrons in orbitals around them.

The five d orbitals in ψ(x, y, z)2 form, with a combination diagram showing how they fit together to fill space around an atomic nucleus.

The graph shows the probability density for various electron orbitals, i.e. the probability one would find an electron if one measured it at a specific (x,y,z).

The shapes of the orbitals of individual atoms allow atoms to bind to each other due to spill over electrical fields. For a diatomic molecule the orbitals will be deformed as far as the single atoms goes but they will still exist.

Suitably aligned f atomic orbitals overlap to form phi molecular orbital (a phi bond)

There exist large varieties of bonds. A similar picture would hold between molecules, their interface will be shared orbitals if the spill over forces are attractive and the molecules can bind to each other. Otherwise they will keep their molecular orbital shape and bounce off each other if interacting .