photosynthetic Spectrophotometry Guess

Despite sun has complicated structure with lots of sphere, the radiation of  sun is similar to 5800K black body.
http://upload.wikimedia.org/wikipedia/commons/4/4c/Solar_Spectrum.png
Based on Wien's Displacement Low,  the peak of emission from 5800K black body is about 500nm (0.0029/5800), which is lime-green. But, due to the atmosphere absorption, the peak of sunlight on sea level is above 500nm, almost 600nm, a kind of redshift.

http://upload.wikimedia.org/wikipedia/commons/7/73/Chlorophyll_ab_spectra.png
While the most common chlorophyll, a and b, have approximate absorbance maxima of 450nm and 650nm. Why not they use the peak of sunlight on the sea level? Ha...the first guess is the chlorophyll's ability, they can only use those band of sunlight due to their special structure. Sounds great...but there is also other kinds of pigment to absorb different spectral band, like chlorophyll D also use infrared light. Why the major chlorophyll absorb lime-green and red rather than the peak of sunlight in yellow. I guess the chlorophyll originate in the early earth where the atmosphere is thin at that time.

However, I can not find the pigment whose absorbance maxima just at 600nm:(...and the difference between 450 and 600 is not so much. Or the chlorophyll reflectance in green and yellow is kind of protection against excessive radiation as radiation inhibition.