34 30         # first data record, number of data records
Reference: JPL Publication 94-26
           Chemical Kinetics and Photochemical Data for Use in Stratospheric
           Modeling
           Evaluation Number 11
           December 15, 1994
           page 150 ff.

CCl2F2 (CFC-12) + hv -> Products

"Tables 39, 40 and 41 list the present recommendations for the cross sections
of CCl4, CCl3F and CCl2F2, respectively.  These data are given by the mean of
the values reported by various groups, i.e., Hubrich et al. [713], Hubrich and
Stuhl [712], Vanlaethem-Meuree et al. [1613, 1614], and Green and Wayne [594],
as well as those referred to in earlier evaluations (CODATA [347]).  Absorption
cross sections for these species over the temperature range 295-210K have also
been reported by Simon et al. [1425].  These results are in generally good
agreement with the present recommendations.  Expressions for the temperature
dependence of the CCl3F and CCl2F2 cross sections are given at the bottom of
Tables 40 and 41, respetively.  These expressions are valid in the wavelength
range of maximum solar photodissociation, i.e., about 190-210 nm, but may not
exactly reproduce the experimental temperature dependences outside this
wavelength range.  However, J-value calculations should not be affected."

sigma(T) = sigma(298) * exp[1E-04 (lambda-184.9)(T-298)]
where sigma(298) = cross section at 298 K
      lambda : nm
      T      : temperature, K

Table 41.  Absorption Cross Sections of CCl2F2
-------------------------------------------------------------------
 lambda (nm)		1E20 sigma (cm^2)
-------------------------------------------------------------------
170			124
172			151
174			171
176			183
178			189
180			173
182			157
184			137
186			104
188			84.1
190			62.8
192			44.5
194			30.6
196			20.8
198			13.2
200			8.84
202			5.60
204			3.47
206			2.16
208			1.52
210			0.80
212			0.48
214			0.29
216			0.18
218			0.12
220			0.068
225			0.022
230			0.0055
235			0.0016
240			0.00029