X-Ray Fluorescence Theory
An electron can be ejected from its atomic orbital by the
absorption of a light wave (photon) of sufficient energy. The energy of
the photon (hv) must be greater than the energy with which the
electron is bound to the nucleus of the atom.
When an inner orbital electron is ejected from an atom, an
electron from a higher energy level orbital will be transferred to the
lower energy level orbital. During this transition a photon maybe
emitted from the atom. This fluorescent light is called the
characteristic X-ray of the element.