Search
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Physical_Chemistry_(LibreTexts)/15%3A_Lasers_Laser_Spectroscopy_and_Photochemistry/15.02%3A_The_Dynamics_of_Transitions_can_be_Modeled_by_Rate_EquationsThis page discusses Einstein's three processes of atomic spectral line formation: spontaneous emission, stimulated emission, and absorption. It explains the behavior of atoms under radiation, focusing...This page discusses Einstein's three processes of atomic spectral line formation: spontaneous emission, stimulated emission, and absorption. It explains the behavior of atoms under radiation, focusing on the interplay of these processes, thermal equilibrium, and the influence of temperature on electron distribution. Population inversion is identified as essential for optical amplification and laser function.
- https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/14%3A_Applications_of_Ultraviolet_Visible_Molecular_Absorption_Spectrometry/14.03%3A_Qualitative_ApplicationsUV/Vis absorption bands result from the absorption of electromagnetic radiation by specific valence electrons or bonds. The energy at which the absorption occurs, and the intensity of that absorption,...UV/Vis absorption bands result from the absorption of electromagnetic radiation by specific valence electrons or bonds. The energy at which the absorption occurs, and the intensity of that absorption, is determined by the chemical environment of the absorbing moiety. UV/Vis spectroscopy also provides ways for studying chemical reactivity.
- https://chem.libretexts.org/Courses/Los_Angeles_Trade_Technical_College/Analytical_Chemistry/2%3A_Analytical_Chemistry_2.0_(Harvey)/11%3A_Spectroscopic_Methods/11.02%3A_Spectroscopy_Based_on_AbsorptionIn absorption spectroscopy a beam of electromagnetic radiation passes through a sample. Much of the radiation passes through the sample without a loss in intensity. At selected wavelengths, however, t...In absorption spectroscopy a beam of electromagnetic radiation passes through a sample. Much of the radiation passes through the sample without a loss in intensity. At selected wavelengths, however, the radiation’s intensity is attenuated. This process of attenuation is called absorption.
- https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/14%3A_Applications_of_Ultraviolet_Visible_Molecular_Absorption_Spectrometry/14.02%3A_Absorbing_SpeciesThere are two general requirements for an analyte’s absorption of electromagnetic radiation. First, there must be a mechanism by which the radiation’s electric field or magnetic field can interact wit...There are two general requirements for an analyte’s absorption of electromagnetic radiation. First, there must be a mechanism by which the radiation’s electric field or magnetic field can interact with the analyte. For ultraviolet and visible radiation, absorption of a photon changes the energy of the analyte’s valence electrons. The second requirement is that the photon’s energy must exactly equal the difference in energy between two of the analyte’s quantized energy states.
- https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/13%3A_Introduction_to_Ultraviolet_Visible_Absorption_Spectrometry/13.03%3A_Effect_of_Noise_on_Transmittance_and_Absorbance_MeasurementsIn absorption spectroscopy, precision is limited by indeterminate errors—primarily instrumental noise—which are introduced when we measure absorbance. Precision generally is worse for low absorbances ...In absorption spectroscopy, precision is limited by indeterminate errors—primarily instrumental noise—which are introduced when we measure absorbance. Precision generally is worse for low absorbances and for high absorbances . We might expect, therefore, that precision will vary with transmittance.
- https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/06%3A_An_Introduction_to_Spectrophotometric_Methods
- https://chem.libretexts.org/Workbench/Pick_Your_Poison%3A_Introduction_to_Materials_Toxicology/30%3A_Energy_Maintenance_and_Environmental_Exchange/30.02%3A_The_Digestive_System/30.2.03%3A_Digestive_System_Processes_and_RegulationThe digestive system uses mechanical and chemical activities to break food down into absorbable substances during its journey through the digestive system. The processes of digestion include six activ...The digestive system uses mechanical and chemical activities to break food down into absorbable substances during its journey through the digestive system. The processes of digestion include six activities: ingestion, propulsion, mechanical or physical digestion, chemical digestion, absorption, and defecation.
- https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/14%3A_Applications_of_Ultraviolet_Visible_Molecular_Absorption_Spectrometry/14.04%3A_Quantitative_ApplicationsThe determination of an analyte’s concentration based on its absorption of ultraviolet or visible radiation is one of the most common quantitative analytical methods. In addition, if an analyte does n...The determination of an analyte’s concentration based on its absorption of ultraviolet or visible radiation is one of the most common quantitative analytical methods. In addition, if an analyte does not absorb UV/Vis radiation—or if its absorbance is too weak—we often can react it with another species that is strongly absorbing.
- https://chem.libretexts.org/Bookshelves/Analytical_Chemistry/Instrumental_Analysis_(LibreTexts)/08%3A_An_Introduction_to_Optical_Atomic_Spectroscopy
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Physical_Chemistry_(LibreTexts)/33%3A_Appendices/33.01%3A_Deriving_Planck's_Distribution_LawThis page discusses Albert Einstein's analysis of emission processes and the derivation of the Planck formula for thermal radiation. It highlights his establishment of relationships between transition...This page discusses Albert Einstein's analysis of emission processes and the derivation of the Planck formula for thermal radiation. It highlights his establishment of relationships between transition probabilities and energy density, as well as the use of the Boltzmann distribution for radiative equilibrium.
- https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Physical_Chemistry_(LibreTexts)/01%3A_The_Dawn_of_the_Quantum_Theory/1.04%3A_The_Hydrogen_Atomic_SpectrumThis page covers the absorption and emission line spectra of hydrogen, focusing on the Balmer series as described by Johann Balmer. It mentions historical contributions from Isaac Newton, Anders Ångst...This page covers the absorption and emission line spectra of hydrogen, focusing on the Balmer series as described by Johann Balmer. It mentions historical contributions from Isaac Newton, Anders Ångström, William Wollaston, and Joseph von Fraunhofer. The text details how line spectra reveal atomic structure and discusses the relationship between wavelength and frequency using wavenumbers.
