Editing Spectroscopy (section)

==== Atoms ====
[[File:Welsbach_Figure_IV_spektroskopische-lytischen-chemie-21.pdf|thumb|Atomic spectra comparison table, from "Spektroskopische Methoden der analytischen Chemie" (1922).]]
[[Atomic spectroscopy]] was the first application of spectroscopy. [[Atomic absorption spectroscopy]] and [[atomic emission spectroscopy]] involve visible and ultraviolet light. These absorptions and emissions, often referred to as atomic spectral lines, are due to [[Atomic structure#Energy levels|electronic transitions]] of outer shell electrons as they rise and fall from one electron orbit to another. Atoms also have distinct x-ray spectra that are attributable to the excitation of inner shell electrons to excited states.

Atoms of different elements have distinct spectra and therefore atomic spectroscopy allows for the identification and quantitation of a sample's elemental composition. After inventing the spectroscope, [[Robert Bunsen]] and [[Gustav Kirchhoff]] discovered new elements by observing their emission spectra. Atomic absorption lines are observed in the solar spectrum and referred to as [[Fraunhofer lines]] after their discoverer. A comprehensive explanation of the [[Hydrogen spectral series|hydrogen spectrum]] was an early success of quantum mechanics and explained the [[Lamb shift]] observed in the hydrogen spectrum, which further led to the development of [[quantum electrodynamics]].

Modern implementations of atomic spectroscopy for studying visible and ultraviolet transitions include [[flame emission spectroscopy]], [[inductively coupled plasma atomic emission spectroscopy]], [[Glow discharge#Use in analytical chemistry|glow discharge spectroscopy]], [[microwave induced plasma]] spectroscopy, and spark or arc emission spectroscopy. Techniques for studying x-ray spectra include [[X-ray spectroscopy]] and [[X-ray fluorescence]].