Lambda max

Unlike IT and NMR spectra, which show many absorptions for a given molecule, UV spectra are usually quite simple—often only a single peak. The peak is usually brocid, and we identify its position by noting the wavelength at the very top of the peak—Amax/ read as "lambda max."... 

Weits I am not saying that its properties must account for the full action spectrum of phase-shifting — it need not be the sole photopigment. However, it is a novel mammalian opsin that has apparently been shown to behave like a photopigment. I don t care about the lambda max in this context. 

That s correct. Incidentally, by computing the area under the curve, you can estimate the total amount of energy the Sun radiates. Now I have a formula for you. We can calculate the wavelength lambda-max at which any star emits the greatest amount of radiation. Brunhilde, display radiation formula. On the flexscreen appears ... 

Here, lambda-max is the wavelength in centimeters and the temperature T is in degrees Kelvin (K). 3... 

Other additive relationships in spectroscopy allows CHESS to predict spectral characteristics of a molecule. These allow calculation of UV lambda-max and e-max values using the methods developed by Woodward and Fieser (4). 

Upon exposure to thermal energy, absorption of light, or involvement in specific chemical reactions, interconversion of lycopene isomers is known to take place. The cis isomers of lycopene, formed by rotation around any of its conjugated double bonds, have chemical and physical characteristics distinctly different from their all-frans counterparts. Some of the differences resulting from trans-to-cis isomerization include lower melting point, decreased color intensity, a shift in the lambda max, smaller extinction coefficients, and the appearance of a new maximum in the ultraviolet spectrum. ... 

A standard UV-VIS spectrophotometer will irradiate a sample with UV and visible light and will generate an absorption spectrum, which plots absorbance as a function of wavelength. The most important feature of the absorption spectrum is the Xmax (pronounced lambda max), which indicates the wavelength of maximum absorption. 

Table V displays the variation of the calculated lambda (max) values for the polyfurans and the corresponding experimental values for the polythiophenes. The calculated lambda(max) values for the polyfurans are seen to be very close to experimental lamlxla(max) values for the polythic henes. This provides additional confidence in the polyfurans as surrogates for the polythiophenes, at least with respect to spectral simulations.

A CNIX3/S simulation on the 3,5-dimethylterfuran predicts a red shift of approximately 10 nm relative to a-T itself. This is the effect expected for methyl groups since they release electrons into the pi-system of the terthiophene. However, the experimental uv-visible spectrum of the 3,5-dimethylterthiophene displays little shift in lambda(max) relative to the spectrum of the unsubstitut terthiophene. The... 

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