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The terms derive from the colours red and blue which form the extremes of the visible light spectrum. The main causes of electromagnetic redshift in astronomy and cosmology are the relative motions of radiation sources, which give rise to the relativistic Doppler effect , and gravitational potentials, which gravitationally redshift escaping ...
The Stokes shift is primarily the result of two phenomena: vibrational relaxation or dissipation and solvent reorganization. A fluorophore is a part of a molecule with a dipole moment that exhibits fluorescence. When a fluorophore enters an excited state, its dipole moment changes, but surrounding solvent molecules cannot adjust so quickly.
When the probe is in an apolar solvent the shift emission is blue, and a red-shifted emission is observed in polar solvents. Due to its structure and its fluorescence characteristics, Laurdan is very useful in studies about lipid bilayer dynamics, more particularly about cell's plasmatic membrane's dynamics.
In spectroscopy, bathochromic shift (from Greek βαθύς (bathys) 'deep' and χρῶμα (chrōma) 'color'; hence less common alternate spelling "bathychromic") is a change of spectral band position in the absorption, reflectance, transmittance, or emission spectrum of a molecule to a longer wavelength (lower frequency). [1]
Because the blue color in the visible spectrum has a shorter wavelength than most other colors, this effect is also commonly called a blue shift. [1] It should not be confused with a bathochromic shift, which is the opposite process – the molecule's spectra are changed to a longer wavelength (lower frequency).
Current research suspects that this red fluorescence is used for private communication between members of the same species. [30] [33] [39] Due to the prominence of blue light at ocean depths, red light and light of longer wavelengths are muddled, and many predatory reef fish have little to no sensitivity for light at these wavelengths. Fish ...
Positive solvatochromism corresponds to a bathochromic shift (or red shift) with increasing solvent polarity. An example of positive solvatochromism is provided by 4,4'-bis(dimethylamino)fuchsone, which is orange in toluene, red in acetone. The main value of the concept of solvatochromism is the context it provides to predict colors of solutions.
Rather than attempt direct measurement of the TDE, Ives and Stilwell (1938) used a concave mirror that allowed them to simultaneously observe a nearly longitudinal direct beam (blue) and its reflected image (red). Spectroscopically, three lines would be observed: An undisplaced emission line, and blueshifted and redshifted lines.