L6 Rich: Fluorescence Spectroscopy Flashcards
what is dissociation?
Breaks into fragments
whats re-emission?
Reverse of absorption process
whats non-radiative decay?
Energy transferred to surrounding molecules
whats radiative decay?
Combination of re-emission and non-radiative decay
what’s ground state?
before energy is absorbed
How does a molecule go from ground state to excited sate?
absorbs energy
in what ways can energy be lost?
dissociation
re-emission
non-radiative decay
radiative decay
what is radiation less dissipation ?
non radiative decay
what are the two radiative decay processes?
fluorescents, phosphorescence
in florescence what do we Start with?
initial absorption
how does florescence radiative decay processe work?
initial absorption, excited electronic state, then it collides with surrounding molecules, stepping down different vibrational energy levels, then emit lights at a lower frequency than incident radiation.
is fluorescence a quick process?
yes
what’s a fluorescence lifetimes?
typically 10^-8 seconds
what’s the most common use of fluorescence?
fluorescence dyes
what are the steps for phophorescence?
initial absorption, excited electronic state, energy lost through collisions etc, steps down vibrational levels, energy level lost like this until gap too big.
