The Helium-4 Atom
The helium atom is the second simplest atom (hydrogen is the simplest), but the extra electron introduces a third "body", so that solution to its wave equation becomes a "three body problem", which has no analytic solution. However, numerical approximations of the equations of quantum mechanics have given a good estimate of the key atomic properties of helium-4, such as its size and ionization energy.
Read more about this topic: Helium-4
Famous quotes containing the word atom:
“Idealism sees the world in God. It beholds the whole circle of persons and things, of actions and events, of country and religion, not as painfully accumulated, atom after atom, act after act, in an aged creeping Past, but as one vast picture, which God paints on the instant eternity, for the contemplation of the soul.”
—Ralph Waldo Emerson (1803–1882)