Chlorophyll: A
group of structurally-similar
molecules
contained in many plants, algae, and cyanobacteria. These
molecules
are used to harvest light energy (
photons)
for
photosynthesis.
Despite their name, chlorophylls do not contain chlorine.
Chlorophylls appear green because their
HOMO-LUMO
gaps are small enough to allow absorption of blue and red
light
photons.