A material(A) that absorbs light at higher wavelength and other(B) absorbs at lower wavelength of light. Absorption peak of A is higher than that of B. Is it possible to compare both materials?
what kind of comparison are you interested in? Sure you can made a comparison. You have to define a parameter.
Absorption is not a material constant. It depends on the thickness of material as well. Thus it is not correct the two materials to be compared only considering the intensity of their absorption peaks. To make some conclusion you should calculate their extinction (absorption) coefficients
Addition
The mol(ecu)ar absorption coefficient and what do you want to compare the intensity absorbed or the number of photons and for what reason and what compounds? because you have to at least have the molecular weight of the compounds then
Possibility for comparison depends from the origin of absorption. Absorption can be own one or impurity one ( semiconductor or solution of dyes correspondentely). Comparison can be done by absorption coefficient in the first case and cross section coefficient in the second case for correspondent wavelengths in the absorption peaks and given concentrations. If both substances are different type You can compare them by their luminescence spectra and quantum yield.
Any successes!
You would need to tabulate the molar absorptivitites at the compounds' respective peak wavelengths in order to compare concentrations.
There are many material parameters one can compare in solution such as
1. Absorbance
2. Concentration
3. Extinction Coefficient
4. Absorption Cross section
5. Oscillator strength
Now it depends on the application.
If you want to compare how strongly one material absorbs over another then absorbance (provided concentration, pathlength are same), extinction coefficient / absorption coefficient , oscillator strength can be used. The absorbance, extinction coefficient, absorption cross section being measured at wavelength maxima.
To determine which of the two is a good absorber. There are different methods
1.Calculate extinction coefficient at lmax (wavelength maxima) for both the samples. You can tell which of the two samples is a good absorber. A molecule with high extinction coefficient is a stronger absorber.
2.Calculate oscillator strength of both the samples (it is related to area under the absorption spectrum)
3. Experimentally determine absorption cross-section of both the samples. This can also be calculated since it is related to extinction cross-section. A molecule with a high absorption cross section is a strong absorber.
For films you have analogous parameters.
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