Absorption Definition and 534 Threads

Absorption spectroscopy refers to spectroscopic techniques that measure the absorption of radiation, as a function of frequency or wavelength, due to its interaction with a sample. The sample absorbs energy, i.e., photons, from the radiating field. The intensity of the absorption varies as a function of frequency, and this variation is the absorption spectrum. Absorption spectroscopy is performed across the electromagnetic spectrum.
Absorption spectroscopy is employed as an analytical chemistry tool to determine the presence of a particular substance in a sample and, in many cases, to quantify the amount of the substance present. Infrared and ultraviolet–visible spectroscopy are particularly common in analytical applications. Absorption spectroscopy is also employed in studies of molecular and atomic physics, astronomical spectroscopy and remote sensing.
There are a wide range of experimental approaches for measuring absorption spectra. The most common arrangement is to direct a generated beam of radiation at a sample and detect the intensity of the radiation that passes through it. The transmitted energy can be used to calculate the absorption. The source, sample arrangement and detection technique vary significantly depending on the frequency range and the purpose of the experiment.
Following are the major types of absorption spectroscopy:

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  1. R

    Exploring the Logic of Black Absorption: Ryan's Experiment

    In school, I have been told that black appears how it is because it absorbs all frequencies of visible light and reflects no frequencies of visible light. Following that logic, if one were to shine a flashlight in a dark room where the walls, ceiling and floor were all black, one would not see...
  2. P

    Rb saturated spectrum and identification of absorption lines

    Hello guys, i have saturated spectrum of Rb. My goal is to identify which lines i see. http://imagizer.imageshack.us/a/img835/8787/xvwr.png So from http://www.opticsinfobase.org/oe/fulltext.cfm?uri=oe-15-10-6293 I have identified that there are to 2 Isotopes: Rb85 and Rb85, further from...
  3. A

    Absorption spectra of T = 0K semiconductor?

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  4. A

    Isotropic absorption and emission

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  5. T

    Power generation through endothermic heat absorption.

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  6. Entanglement

    Why is cold gas used for producing an absorption line spectrum?

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  7. D

    Using dark tiles to heat a pool via absorption of solar energy

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  8. N

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  9. marellasunny

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  10. TESL@

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  11. Z

    Why do stars show absorption lines?

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  12. D

    IR and UV absorption of materials

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  13. L

    Understanding Emission and Absorption Power in Three-Body Systems

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  14. Q

    Can Waste Heat from an Oven Power an Absorption Refrigerator?

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  15. Entanglement

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  16. E

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  17. M

    Inelastic and elastic scattering and absorption.

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  18. C

    Localized absorption of photons and carrier generation

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  19. N

    Absorption And Emission Of Light According To Quantum Mechanics

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  20. A

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  21. C

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  22. U

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  23. G

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  24. gfxroad

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  25. O

    How Can I Design an IR Absorption Surface with No Reflectivity?

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  26. S

    Optical path length change due to absorption

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  27. M

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  28. C

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  29. M

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  30. A

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  31. R

    Reflection and absorption in matte black vs. shiny black objects

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  32. M

    Archived Analyzing Power Absorption in a Lightly Damped Harmonic Oscillator

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  33. B

    Is absorption an axiom for a boolean algebra?

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  34. A

    Fourier Series and Absorption Questions?

    Sorry if I am posting in the wrong place. I'm really interested in the Fourier series, but I'm not an expert on it yet. I am very well aware yoy can do it with sound waves, but can you manipulate any other waves? What about light waves? And for absorption, how can you measure the...
  35. M

    Determine Radiation pressure given the fraction of total absorption

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  36. W

    SAR (special absorption rate) & frequency

    Hi we know the relation between wavelength, frequency and energy : The greater the energy, the larger the frequency and the shorter (smaller) the wavelength -> E=h\upsilon On the other side, SAR is common property that measures absorbed energy. Now if we calculating SAR for human brain...
  37. A

    Radiation absorption and temperature changes in matter

    Hi there, I've been studying mechanisms by which high-energy radioactive decay products (beta particles, x-rays, gamma rays) are attenuated as they pass through matter. From my readings in introductory and intermediate level textbooks, the general mechanisms by which these particles and rays...
  38. MarkFL

    MHB Heather's Mathematical Model Question on Herbicide Absorption

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  39. M

    Coeliac disease, vitamin absorption

    does anyone know anything about coeliac disease and malabsorption syndrome/disease? it can really affect life. I've been seeing specialist doctors including GI specialists for years, one cure for coeliac is a no wheat/gluten diet
  40. W

    What is the Dynamic Scaling Theory for Ultrasonic Absorption in Binary Mixtures?

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  41. B

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  42. C

    Absorption coefficient of aluminium for microwaves

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  43. I

    Mechanism behind photon absorption and photon emission

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  44. C

    589.3nm +/- 0.3nm Absorption Lasing Medium?

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  45. H

    How does temperature affect excitonic absorption?

    As far as I know, free electron-hole or excitons can be created by absorbing a photon of relevant energy. So dissociation of excitons shouldn't make any effects on absorption because dissociation happens after the absorption. Nevertheless I saw in some texts that in the limit of the temperatures...
  46. A

    Probability of Brownian particle absorption

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  47. B

    Excitation and Absorption spectra

    Hello, am working with luminescence spectra, including excitation and emission spectra. When you makes an initial characterization of a sample should be done first? an absorption spectrum? At what wavelength excitation should be performed to see the desired effect? Particularly when...
  48. U

    How Is the Rydberg Constant Calculated from Photon Absorption Wavelengths?

    Homework Statement The following photon wavelengths are observed in absorption at room temperature from an ionized atomic gas with a single electron orbiting the nucleus: λ= 13:5 nm, 11:4 nm, 10:8 nm. Use this data to determine the effective Rydberg constant and the nuclear charge...
  49. E

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  50. M

    What Do Peaks in Gamma Radiation Absorption Data Indicate?

    After performing this experiment, we will get different peaks on the computer screen, where on x-axis lies thickness of the absorber and on the y-axis the nb of channels. What do these represent exactly? Why do we have a high peak and a medium sized one? What are the significances of each...
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