light absorption question

[echoyjeff222]

Does absorbing light always mean that the electrons are promoted into a higher level? Could a compound absorb energy that doesn't exactly correspond to an energy gap between energy levels and thus not promote an electron? Or does the definition of "absorb" mean electrons are promoted?

In reference to this question ...

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[Cawolf]

Yes, by definition absorption of light means that that the electron gains energy.

If it does not match the discrete energy level change ( such as n = 1 to n=2) then it will not be absorbed.

So in that question, A and C may both be true - but it does not always ionize - it does always excite the electrons though (if it excites them to n = infinity then it is ionized).

Absorption spectra show what wavelengths match the discrete energy levels - all other colors pass through that don't match.