C2H4 (+M) -> H2 + C2H2 (+M)

k_inf = 8.00E+12 T^0.44 exp(-88770 cal/mol /RT) s^(-1)

F_cent = (1-0.735) exp(-T/180) + 0.735 exp(-T/1035) + exp(-5417/T)

Third-body efficiencies:

N2                    1.0 
H2     Enhanced by    2.0 
H2O    Enhanced by    6.0 
CH4    Enhanced by    2.0 
CO     Enhanced by    1.5 
CO2    Enhanced by    2.0 
C2H6   Enhanced by    3.0 
Ar     Enhanced by    0.7 

SOURCE:

The expression for k_inf is from Tsang and Hampson (1986)

k_o and F_cent for N2 are calculated by the method of Troe (1977):
delta-E(0 K) = 88.0 kcal/mol
<delta E> = 0.30 kcal/mol
The Lennard-Jones parameters: sigma (C2H2-N2) = 4.0 A, epsilon = 126 K
v = 3105, 3069, 3019, 2990, 1623, 1444, 1342, 1055, 995, 950, 943, 825 cm^(-1)

The resulting k_o expression was divided by 3 in order to fit the decompostion rate data in Ar at 2000 K from Tanzawa and Gardiner (1980) and Zelson et al.(1994).

COMMENTS:

The pressure broadening is expressed in the Troe form.

REFERENCES:

Tsang and Hampson (1986)

Tsang, W., and Hampson, R.F. (1986) J. Phys. Chem. Ref. Data 15, 1087.

Troe (1977)

Troe, J. (1977) J.Chem.Phys. 66, 4745.

Tanzawa and Gardiner (1980)

Tanzawa, T., and Gardiner, W.C. (1980) Combust. Flame 39, 241.

Zelson et al.(1994)

Zelson, L.S., Davidson, D.F., and Hanson, R.K. (1994) J. Quant. Spectrosc. Radiat. Transfer 52, 31.

                        PRESSURE = 0.1 atm N2  
______________________________________________________________________
    Temp      delta-S     delta-H      kf          kr         Keq     
     (K)    (cal/mol K)  (kcal/mol) ----(mol,cm3,s)-----   (mol/cm3)  
______________________________________________________________________
                                                                      
     300        26.9        42.0    8.60E-52    1.13E-22    7.62E-30
     500        30.2        43.3    1.23E-25    1.06E-08    1.16E-17
    1000        32.2        44.6    1.40E-06    5.95E+01    2.35E-08
    1500        32.3        44.7    8.94E-01    3.15E+04    2.84E-05
    2000        32.1        44.4    3.27E+02    3.64E+05    8.98E-04
    2500        31.9        44.0    7.12E+03    1.07E+06    6.65E-03
    3000        31.8        43.7    3.94E+04    1.64E+06    2.41E-02
______________________________________________________________________


                        PRESSURE = 1 atm N2    
______________________________________________________________________
    Temp      delta-S     delta-H      kf          kr         Keq     
     (K)    (cal/mol K)  (kcal/mol) ----(mol,cm3,s)-----   (mol/cm3)  
______________________________________________________________________
                                                                      
     300        26.9        42.0    1.64E-51    2.15E-22    7.62E-30
     500        30.2        43.3    1.71E-25    1.47E-08    1.16E-17
    1000        32.2        44.6    3.50E-06    1.49E+02    2.35E-08
    1500        32.3        44.7    3.24E+00    1.14E+05    2.84E-05
    2000        32.1        44.4    1.61E+03    1.79E+06    8.98E-04
    2500        31.9        44.0    4.64E+04    6.98E+06    6.65E-03
    3000        31.8        43.7    3.09E+05    1.28E+07    2.41E-02
______________________________________________________________________


                        PRESSURE = 10 atm N2   
______________________________________________________________________
    Temp      delta-S     delta-H      kf          kr         Keq     
     (K)    (cal/mol K)  (kcal/mol) ----(mol,cm3,s)-----   (mol/cm3)  
______________________________________________________________________
                                                                      
     300        26.9        42.0    1.99E-51    2.61E-22    7.62E-30
     500        30.2        43.3    1.86E-25    1.61E-08    1.16E-17
    1000        32.2        44.6    5.23E-06    2.22E+02    2.35E-08
    1500        32.3        44.7    9.24E+00    3.25E+05    2.84E-05
    2000        32.1        44.4    5.99E+03    6.67E+06    8.98E-04
    2500        31.9        44.0    2.14E+05    3.21E+07    6.65E-03
    3000        31.8        43.7    1.90E+06    7.90E+07    2.41E-02
______________________________________________________________________