Absorption cross section for molecular chlorine (CL2)
From Finlayson-Pitts and Pitts, "Chemistry of the upper 
and lower atmosphere," Academic Press, 1999
Data  is taken from JPL97
wavelength	1e20 cm2 molec-1
260	0.20
270	0.82
280	2.6
290	6.2
300	11.9
310	18.5
320	23.7
330	25.5
340	23.5
350	18.8
360	13.2
370	8.4
380	5.0
390	2.9
400	1.8
410	1.3
420	0.96
430	0.73
440	0.54
450	0.38
460	0.26
470	0.16