CH2 + CO (+M) -> CH2CO (+M)

k_o = 2.69E+33 T^(-5.11) exp(-7095 cal/mol /RT) cm^6/mol^2 s

k_inf = 8.10E+11 T^0.5 exp(-4510 cal/mol /RT) cm3/mol s

F_cent = (1-0.591) exp(-T/275) + 0.591 exp(-T/1226) + exp(-5185/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:

Results of an RRKM calculation done assuming a 4.5 kcal/mol barrier to recombination, based on the decomposition data of Wagner and Zabel (1971) and Frank et al. (1986).

RRKM calculations with these parameters:
delta-E(0 K) = 4.5 kcal/mol
delta-H(0 K) = -76.2 kcal/mol
<delta E> = 0.30 kcal/mol
The Lennard-Jones parameters: sigma (CH2CO-N2) = 4.16 A, epsilon = 160 K
Adiabatic I = 51.0, 49.1 amu-A^2; sigma = 2
Active K-rotor I = 1.8 amu-A^2, sigma = 1
v = 3166, 3070, 2152, 1388, 1118, 977, 588, 528, 433 cm^(-1)

Transition state parameters:
Active K-rotor I = 1.8 amu-A^2, sigma = 1
2-D hindered rotors I = 2.2 , 0.25 amu-A^2 (94%); sigma = 1, 1
Adiabatic I+ = 306, 295 amu-A^2; sigma = 2 (I+/I = 6.0)
v = 3120, 2950, 2733, 1050 cm^(-1)

COMMENTS:

Comparison to CH2CO decomposition data of Wagner and Zabel (1971) and Frank et al. (1986) in Ar (in cm3, mol, s units):

T/K	k_inf		k_o
T/K	Wagner and Zabel (1971)	GRI-Mech	Wagner and Zabel (1971)	Frank et al. (1986)	GRI-Mech
1400	2500	2600	2.3E6	3.8E6	6.0E6
1650	1.2E5	2.0E5	5.3E7	8.5E7	2.0E8
1850	2.4E5	3.2E5	3.6E8	5.5E8	1.6E9

T/K k (200 atm) k (5 atm)

Wagner and
Zabel (1971) GRI-Mech Wagner and
Zabel (1971) GRI-Mech

1400 900 700 65 69

1650 3.0E4 3.0E4 1800 2460

1850 2.4E5 3.2E5 1.0E4 1.77E4

T/K	k (200 atm)	k (5 atm)
Wagner and Zabel (1971)	GRI-Mech	Wagner and Zabel (1971)	GRI-Mech
1400	900	700	65	69
1650	3.0E4	3.0E4	1800	2460
1850	2.4E5	3.2E5	1.0E4	1.77E4

The pressure broadening is expressed in the Troe form.

REFERENCES:

Wagner and Zabel (1971)

Wagner, H.Gg., and Zabel, F. (1971) Ber. Bunsenges. Phys. Chem. 71, 114.

Frank et al. (1986)

Frank, P., Bhaskaran, K.A., and Just, T. (1986) J. Phys. Chem. 90, 2226.

                        PRESSURE = 0.1 atm N2  
______________________________________________________________________
    Temp      delta-S     delta-H      kf          kr         Keq     
     (K)    (cal/mol K)  (kcal/mol) ----(mol,cm3,s)-----   (cm3/mol)  
______________________________________________________________________
                                                                      
     300       -35.9       -78.8    3.03E+09    3.67E-45    8.26E+53
     500       -36.8       -79.1    3.03E+10    2.20E-21    1.38E+31
    1000       -36.3       -78.7    2.32E+10    1.56E-04    1.49E+14
    1500       -35.5       -77.7    6.82E+09    1.53E+01    4.45E+08
    2000       -34.8       -76.5    2.33E+09    2.53E+03    9.21E+05
    2500       -34.2       -75.2    9.43E+08    3.73E+04    2.53E+04
    3000       -33.7       -73.8    4.28E+08    1.72E+05    2.49E+03
______________________________________________________________________


                        PRESSURE = 1 atm N2    
______________________________________________________________________
    Temp      delta-S     delta-H      kf          kr         Keq     
     (K)    (cal/mol K)  (kcal/mol) ----(mol,cm3,s)-----   (cm3/mol)  
______________________________________________________________________
                                                                      
     300       -35.9       -78.8    5.70E+09    6.91E-45    8.26E+53
     500       -36.8       -79.1    8.10E+10    5.87E-21    1.38E+31
    1000       -36.3       -78.7    1.35E+11    9.07E-04    1.49E+14
    1500       -35.5       -77.7    4.98E+10    1.12E+02    4.45E+08
    2000       -34.8       -76.5    1.89E+10    2.05E+04    9.21E+05
    2500       -34.2       -75.2    8.20E+09    3.24E+05    2.53E+04
    3000       -33.7       -73.8    3.90E+09    1.57E+06    2.49E+03
______________________________________________________________________


                        PRESSURE = 10 atm N2   
______________________________________________________________________
    Temp      delta-S     delta-H      kf          kr         Keq     
     (K)    (cal/mol K)  (kcal/mol) ----(mol,cm3,s)-----   (cm3/mol)  
______________________________________________________________________
                                                                      
     300       -35.9       -78.8    6.84E+09    8.28E-45    8.26E+53
     500       -36.8       -79.1    1.49E+11    1.08E-20    1.38E+31
    1000       -36.3       -78.7    4.65E+11    3.12E-03    1.49E+14
    1500       -35.5       -77.7    2.64E+11    5.93E+02    4.45E+08
    2000       -34.8       -76.5    1.26E+11    1.37E+05    9.21E+05
    2500       -34.2       -75.2    6.33E+10    2.50E+06    2.53E+04
    3000       -33.7       -73.8    3.30E+10    1.33E+07    2.49E+03
______________________________________________________________________

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