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  2. Absorption edge - Wikipedia

    en.wikipedia.org/wiki/Absorption_edge

    In physics, an absorption edge (also known as an absorption discontinuity or absorption limit) is a sharp discontinuity in the absorption spectrum of a substance. These discontinuities occur at wavelengths where the energy of an absorbed photon corresponds to an electronic transition or ionization potential .

  3. Ultraviolet–visible spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet–visible...

    A UV-Vis spectrophotometer is an analytical instrument that measures the amount of ultraviolet (UV) and visible light that is absorbed by a sample. It is a widely used technique in chemistry, biochemistry, and other fields, to identify and quantify compounds in a variety of samples.

  4. Urbach energy - Wikipedia

    en.wikipedia.org/wiki/Urbach_energy

    The Urbach Energy, or Urbach Edge, is a parameter typically denoted , with dimensions of energy, used to quantify energetic disorder in the band edges of a semiconductor. It is evaluated by fitting the absorption coefficient as a function of energy to an exponential function.

  5. UV-Vis absorption spectroelectrochemistry - Wikipedia

    en.wikipedia.org/wiki/UV-Vis_absorption_spectro...

    UV-Vis absorption SEC is a recent technique that is continuously evolving. However, many advantages have been observed over other techniques. However, many advantages have been observed over other techniques.

  6. Electromagnetic absorption by water - Wikipedia

    en.wikipedia.org/wiki/Electromagnetic_absorption...

    The absorption band at 698 nm (14300 cm −1) is a 3rd overtone (n=4). It tails off onto the visible region and is responsible for the intrinsic blue color of water. This can be observed with a standard UV/vis spectrophotometer, using a 10 cm path-length.

  7. UV detectors - Wikipedia

    en.wikipedia.org/wiki/UV_detectors

    The vast majority of liquid chromatographic systems are equipped with ultraviolet (UV) absorption detectors. The most common UV-Vis detectors used are variable wavelength detectors (VWD), photo diode array detectors (PDA), and diode array detectors (DAD). [4] Variable wavelength detectors decide in advance which wavelength is needed for the ...

  8. Woodward's rules - Wikipedia

    en.wikipedia.org/wiki/Woodward's_rules

    With the aid of these rules the UV absorption maximum can be predicted, for example in these two compounds: [8] In the compound on the left, the base value is 214 nm (a heteroannular diene). This diene group has 4 alkyl substituents (labeled 1,2,3,4) and the double bond in one ring is exocyclic to the other (adding 5 nm for an exocyclic double ...

  9. Fluoride glass - Wikipedia

    en.wikipedia.org/wiki/Fluoride_glass

    Fluoride fiber's optical properties can be determined by the intrinsic and extrinsic sources of loss. There are three sources of intrinsic loss for fluoride glass: UV absorption edge, Rayleigh scattering, and multiphonon absorption. [1] At short wavelengths within the UV and visible spectrum, the UV absorption edge is the dominant effect.