Question
The more conjugated the compound, the ____ the wavelength of maximum absorbance.
Answer
The more conjugated the compound, the lower the energy of the transition and the greater the wavelength of maximum absorbance.
In Summary: UV and visible spectroscopy can be used to detect electronic excitations in
conjugated molecules. With an increasing number of molecular orbitals, there is an increasing
variety of possible transitions and hence number of absorption bands. The band of longest
wavelength is typically associated with the movement of an electron from the highest occupied
to the lowest unoccupied molecular orbital. Its energy decreases with increasing conjugation.
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Infrared (IR) spectroscopy measures ____.
Molecular vibrations can be seen as ____.
To record an IR spectrum, i____e is measured.
The infrared light range runs from λ = ____.
The useful absorptions for infrared spectroscopy occur at wavelengths of ____ nm.
On an IR spectrum, we use an analog of ____ called wavenumber.