ultraviolet spectroscopy

chemistry

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July 14, 2026

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Ultraviolet (UV) spectroscopy is a technique used in chemistry to study molecules. It involves measuring how much ultraviolet light a substance absorbs at different wavelengths. This is based on Beer's law, which relates absorption to concentration, and Bouguer's law, which describes absorption by layers of a medium.1

While many organic compounds are transparent to UV light, those with conjugated pi bonds absorb it. UV-visible spectroscopy is particularly useful for detecting and measuring the concentration of colorless substances in solution and for providing structural information about molecules containing these conjugated systems. Instruments called spectrometers measure the wavelengths of light absorbed by molecules, providing insights into their energy levels and structure.12

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spectroscopy
Visible and ultraviolet spectroscopy
Colours as perceived by the sense of vision are simply a human observation of the inverse of a visible absorption spectrum. The underlying phenomenon is that of an electron being raised from a low-energy
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Colours as perceived by the sense of vision are simply a human observation of the inverse of a visible absorption spectrum. The underlying phenomenon is that of an electron being raised from a low-energy
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heterocyclic compound
Ultraviolet, infrared, nuclear magnetic resonance, and mass spectra
The ultraviolet spectrum of an organic compound (the pattern of its light absorption in the ultraviolet region of the spectrum) is characteristic of the π-electron system of the molecule—i.e., of the arrangement of double bonds within the structure. The ultraviolet spectra of heteroaromatic compounds show general…
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The ultraviolet spectrum of an organic compound (the pattern of its light absorption in the ultraviolet region of the spectrum) is characteristic of the π-electron system of the molecule—i.e., of the arrangement of double bonds within the structure. The ultraviolet spectra of heteroaromatic compounds show general…
Read More

chemical compound
Ultraviolet and visible (UV-visible) spectroscopy
Most organic compounds are transparent to the relatively high-energy radiation that constitutes the ultraviolet (200–400 nm) and visible (400–700 nm) portion of the electromagnetic spectrum, and consequently they appear colourless in solution. This is because the electrons in the σ…
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Most organic compounds are transparent to the relatively high-energy radiation that constitutes the ultraviolet (200–400 nm) and visible (400–700 nm) portion of the electromagnetic spectrum, and consequently they appear colourless in solution. This is because the electrons in the σ…
Read More