Do atoms ever actually touch each other?

It seems to be a straightforward question but results in a complicated answer. First, we need to revisit the meaning of the term "touch". Usually, we define as two body touching each other if the border of one object is in contact with another. But on an atomic level, things are notso black and white; they don't work as we see in our day to day life (Classical Physics). In the quantum realm, we can not precisely define the border, path or position of an atom. Remember,an atom is mostly space. All we can calculate is the probability of finding an electron at a specific position after applying some approximations in Density functional theory. Now, since we don't have a clear boundary, so the term "touch" becomes meaningless at the atomic level. When the atoms come closer to each other, they interact via electromagnetic forces and results in the formation of different electronic/band/bond structure in a solid. read less