All Questions
Tagged with absorption spectroscopy
61
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X-ray absorption edge, accurate theoretical predition possible?
It is well known that in X-ray absorption spectroscopy, the absorption spectrum shows discontinuities at some critical frequencies.
Is it possible to predict locations of these jumps theoretically? I ...
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Why escape peak positions are calculated using emission energy and not absorbing energy?
For a X-ray monocromatic source, escape peaks energy positions are described by the difference between the incident energy and the fluorescence ($K_{\alpha}$ for example), like $E_{Escape Peak} = E_0 -...
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What happens after bulk gold absorbs a photon with its energy at the band gap or higher (wavelength < 500 nm)?
As is explained in the answers of this question: Why are most metals gray/silver? nicely, the responsible transition occurs between the 5d orbital and the 6s orbital, which is relativistically shrunk ...
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What determines the wavelength in absorption?
When looking at absorption or reflectance spectra, say in the range of 400nm to 2500nm, you can see peaks (or dips) at certain wavelengths, that are characteristic for the material absorbing and ...
- 111
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How do we know that the Sun is 71% Hydrogen by mass from emission/absorption spectra?
In my Intro to Astronomy ("intro" is very important, please keep responses as simple as possible) course, we're currently learning about light and electron orbitals and such, and I came ...
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450nm peak absorption [closed]
I am looking for an oxide compound (metal oxide, or similar preferably inorganic) which shows light peak absorption at 450 nm. I have troubles in finding the right compound, as most of the oxides have ...
- 113
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Absorbance spectrum of common metal oxides
I am looking into metal oxides particles, and I wonder where can I find the absorbance spectrum of visible light of common avaiable metal oxides?
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What is the influence of humidity on NDIR $\rm CO_2$ measurements?
The Question
I would like to use an NDIR $\rm CO_2$ sensor to measure $\rm CO_2$ in the 0.1-3% range. However, in the course of my experiments, humidity may vary from ambient (50-60%) up to nearly 100%...
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Convolution or addition? Proper way to model overlapping absorption line profiles
Suppose you obtain a measured spectral line shape (let's call it 'envelope') which appears as a skewed/asymmetric voigt profile. You know physically that the envelope line profile has this skew ...
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How do degenerate states affect molecular absorption?
Molecular absorption of light is related to the transition dipole moment according to the equation from Hilborn, 1982:
$$\sigma(\omega)=\frac{\pi \omega}{3\epsilon_0\hbar c} \frac{g_2}{g_1}\mu^2\rho(\...
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Absorption Spectra of Atmospheric Gases
From this previous Stackexchange question:
Is a detailed absorption spectrum available for carbon dioxide from 300-1100nm?
and this paper:
https://www.osti.gov/servlets/purl/1613653
as well as this ...
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2
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Why do different metals glow with different colours if all solids have the same emission spectrum?
Why do different metals glow with different colors if all solids have the same emission spectrum? According to my teacher, all solids have the same emission spectrum at the same temperature due to ...
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Absorption spectrum dependence on concentration/pressure
I am having difficulties understanding the relation between absorption spectrum and gas concentration. The online resources I found, including many questions here, do not clarify my doubts.
Take for ...
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What accounts for a Lyman-break for all wavelengths shorter than 91.2nm if the Lyman limit is the highest energy photon that Neutral hydrogen absorbs?
From this description of Lyman-break galaxies, I don't understand how:
...radiation at higher energies than the Lyman limit at 912 Å is almost completely absorbed by neutral gas around star-forming ...
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Why does an element show an absorption spectrum?
We know that the colour we see of different objects around us is because they absorb all the radiation except a specific wavelength which gets reflected back to us. So, in an emission spectrum, when ...
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