"Conversely, when all heat has been driven from a substance, as Professor Keesom almost did last week, it may be that "matter" will explode into those universal waves which man at present can call only "nothingness." What the violence of such an explosion might be, no man can guess but experimenter Keesom may yet find out."
If you consider during the first nano seconds of the Big Bang when temperatures were at their highest in history (and energy at its most dense), all of the base forces were combined.
As the energy of the early universe expanded and became less dense, the atomic forces (strong, weak, etc) froze and separated out of the dense energy and the unifying parent force. As the atomic forces became separated, quanta of energy started forming into sub-sub-atomic particles which further combined into sub-atomic particles like protons, neutrons, and electrons. These then combined to form mainly hydrogen with trace amounts of helium and lithium.
Its not till later after the first few generations of mega-stars that other elements formed (oxygen, carbon, iron, etc).
So based on all of this, from everything I know particle physics seems to be the result of energy moving into lower states over the time scale of the universe. Because of this, I don't think that if you cool an atom to absolute zero (which is supposed to be impossible but I don't know why), that the atom will disperse. The removal of energy doesn't seem to make the fundamental forces disappear, so all you get is a very cold atom of helium that just doesn't move at all.