Stark spectroscopy

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Stark spectroscopy (sometimes known as electroabsorption/emission spectroscopy) is a form of spectroscopy based on the Stark effect. In brief, this technique makes use of the Stark effect (or electrochromism) either to reveal information about the physiochemical or physical properties of a sample using a well-characterized electric field or to reveal information about an electric field using a reference sample with a well-characterized Stark effect.

Spectroscopy study of the interaction between matter and electromagnetic radiation

Spectroscopy is the study of the interaction between matter and electromagnetic radiation. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, by a prism. Later the concept was expanded greatly to include any interaction with radiative energy as a function of its wavelength or frequency, predominantly in the electromagnetic spectrum, though matter waves and acoustic waves can also be considered forms of radiative energy; recently, with tremendous difficulty, even gravitational waves have been associated with a spectral signature in the context of LIGO and laser interferometry. Spectroscopic data are often represented by an emission spectrum, a plot of the response of interest as a function of wavelength or frequency.

Stark effect optical phenomenon in physics

The Stark effect is the shifting and splitting of spectral lines of atoms and molecules due to the presence of an external electric field. It is the electric-field analogue of the Zeeman effect, where a spectral line is split into several components due to the presence of the magnetic field. Although initially coined for the static case, it is also used in the wider context to describe effect of time-dependent electric fields. In particular, the Stark effect is responsible for the pressure broadening of spectral lines by charged particles in plasmas. For majority of spectral lines, the Stark effect is either linear or quadratic with a high accuracy.

The use of the term "Stark effect" differs between the disciplines of chemistry and physics. Physicists tend to use the more classical definition of the term (see Stark effect), while chemists usually use the term to refer to what is technically electrochromism. [1] In the former case, the applied electric field splits the atomic energy levels and is the electric field analog of the Zeeman effect. However, in the latter case, the applied electric field changes the molar absorption coefficient of the sample, which can be measured using traditional absorption or emission spectroscopic methods. This effect is known as electrochromism.


Electrochromism is the phenomenon displayed by some materials of reversibly changing colour stimulated by redox reactions. Various types of materials and structures can be used to construct electrochromic devices. Electrochromic displays are based on any material that changes color depending on the applied potential.

Zeeman effect effect of splitting a spectral line into several components in the presence of a static magnetic field

The Zeeman effect, named after the Dutch physicist Pieter Zeeman, is the effect of splitting a spectral line into several components in the presence of a static magnetic field. It is analogous to the Stark effect, the splitting of a spectral line into several components in the presence of an electric field. Also similar to the Stark effect, transitions between different components have, in general, different intensities, with some being entirely forbidden, as governed by the selection rules.

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  1. Liptay, W. Berichte der Bunsengesellschaft für physikalische Chemie. 1974, 80, 207-217.; Liptay, W. Excited States. 129-159.