Is there a way to calculate how close two atoms can get before their electrons start to repel each other and prevent atoms from getting closer together. I'm guessing this is dependent on the size of the atom and it's number of protons and electrons. I am asking because I am working on a sonoluminescence project and papers say that a sonoluminescent bubble reaches minimum size when the atoms in the bubble cannot be compressed anymore due to electron repulsion. So what I want to know is exactly how far is each atom from each other where the electron repulsion will stop the bubble from compressing further. Thank you!