Polarity absorptivity +_+

  • Thread starter schordinger
  • Start date
  • Tags
    Polarity
In summary, polarity refers to the separation of electric charge within a molecule, resulting in a positive and negative end. It can affect absorptivity by influencing the strength of intermolecular forces, such as dipole-dipole interactions, and is determined by the molecule's chemical structure, types of bonds present, and polarity. Polarity can also affect the color of a molecule by impacting the wavelengths of light it absorbs, which can be measured through techniques like UV-visible spectroscopy.
  • #1
schordinger
23
0
changing absorptivity

Solvent polarity would affect the wavelength of max absorption peak, but how??

and How the solvent affect the absorption coefficient??

is that related sth called Franck-Condon factor??

Also, Flourescent quantum yield also depend on the solvent polarity??
How?? and Why??

Thx
 
Last edited:
Chemistry news on Phys.org
  • #2
Actually...

I am really confuse that why some compound would fluoresce stronger in polar environment (solvent) than non-polar solvent, like Fluorescein, and some other compound, like Acrylodan would fluoresce stronger in Non-polar environment...??


It seem that Fluorescein is a interesting compound...
 
  • #3


Solvent polarity can affect the wavelength of maximum absorption peak by changing the electronic structure of the molecule. When a molecule is placed in a polar solvent, the solvent molecules can interact with the electronic charge distribution of the molecule, causing a shift in the energy levels and consequently, a shift in the wavelength of maximum absorption peak.

The solvent can also affect the absorption coefficient, which is a measure of how strongly a molecule absorbs light at a particular wavelength. This is because the solvent can influence the molecular vibrations and rotations, which in turn affect the absorption of light by the molecule.

The Franck-Condon factor is related to the absorption process, specifically in the context of electronic transitions. It describes the probability of a molecule undergoing an electronic transition without any simultaneous changes in its vibrational or rotational energy levels. In other words, it represents the overlap between the initial and final electronic wavefunctions of the molecule.

The solvent polarity can also affect the fluorescent quantum yield, which is a measure of the efficiency of a molecule in converting absorbed light into fluorescence. This is because the solvent can influence the relaxation processes of the excited state of the molecule, which can affect the emission of fluorescence. A polar solvent can enhance the rate of non-radiative relaxation, leading to a decrease in the fluorescence quantum yield.

Overall, the solvent polarity can have a significant impact on the absorption and emission properties of a molecule. Understanding these effects can help in the design and optimization of molecules for various applications, such as in organic solar cells and fluorescent sensors.
 

What is polarity?

Polarity refers to the separation of electric charge within a molecule, resulting in a positive and negative end.

How does polarity affect absorptivity?

Polarity can affect absorptivity by influencing the strength of intermolecular forces, such as dipole-dipole interactions, which can impact a molecule's ability to absorb light.

What factors determine the absorptivity of a molecule?

The absorptivity of a molecule is determined by its chemical structure, the types of bonds present, and the polarity of the molecule.

Can polarity affect the color of a molecule?

Yes, polarity can affect the color of a molecule by influencing the wavelengths of light that the molecule absorbs. This can result in a molecule appearing a certain color to the human eye.

How is polarity absorptivity measured?

Polarity absorptivity can be measured using techniques such as UV-visible spectroscopy, which measures the absorbance of light by a molecule at different wavelengths.

Similar threads

Replies
2
Views
15K
Replies
8
Views
4K
Replies
115
Views
7K
  • Atomic and Condensed Matter
Replies
0
Views
725
Replies
1
Views
2K
  • Chemistry
Replies
3
Views
2K
Replies
1
Views
868
Replies
4
Views
1K
Replies
3
Views
985
Replies
10
Views
978
Back
Top