IUPAC Subcommittee on Gas Kinetic Data Evaluation

Providing evaluated kinetic data on the web since 1999.

IUPAC Subcommittee on Gas Kinetic Data Evaluation

Website: http://www.iupac-kinetic.ch.cam.ac.uk/ See website for latest evaluated data. Datasheets can be downloaded for personal use only and must not be retransmitted or disseminated either electronically or in hardcopy without explicit written permission.

This datasheet last evaluated: 2002-03-09 ; last change in preferred values: 2002-03-09 ; last peer-reviewed publication: 2004-03-09


NO2 + NO3 + MN2O5 + M(1) Δ Hο = -95.6 kJ mol-1

Rate Coefficient Data: Low-pressure rate coefficients

Absolute Rate Coefficients

Rate Coefficient (k0) / Temperature / ReferenceTechniques and Comments
cm3molecule-1s-1Kelvin
9.6×10 -33 exp(1550/T) [N 2 ]262–295Connell and Johnston, 1979(a)
1.7×10 -30 [N 2 ]298
1.35×10 -32 exp(1270/T) [N 2 ]285–384Viggiano et al., 1981(b)
9.6×10 -31 [N 2 ]298
(4.5 ± 1.1)×10 -30 (T/300) -(3.4±1.3) [N 2 ]236–358Kircher et al., 1984FP-A (c)
2.12×10 -30 [N 2 ]298Smith et al., 1985DF-A (d)
2.8×10 -30 (T/300) -3.5 [N 2 ]236–358Orlando et al., 1991DF-LIF (e)

Comments

(a) From study of N 2 O 5 decomposition. Static reaction vessel with multi-reflection White-cell optical arrangement for the time-resolved detection of N 2 O 5 by IR absorption at 8.028 μm. Converted to recombination rate coefficients with the equilibrium constant K c = 8.4×10 26 exp(-11180/T) molecule cm -3 from Graham and Johnston (1978).

(b) From study of N 2 O 5 decomposition. Flow system reactors of various size. N 2 O 5 was detected by ion-molecule reactions in a flowing afterglow system. Measurements were carried out at [N 2 ] = 2.5×10 17 to 2.7×10 19 molecule cm -3 . Converted to recombination rate coefficients with the equilibrium constant K c = 8.4×10 26 exp(-11180/T) molecule cm -3 from Graham and Johnston (1978).

(c) Visible absorption of NO 3 monitored under pseudo-first order conditions. Falloff curve measured over the pressure range 27–930 mbar (20–700 Torr) and extrapolated using reduced falloff curve representation with F c = 0.34 at 298 K.

(d) Visible absorption of NO 3 monitored. Pressure range 1.3–10.7 mbar (1–8 Torr) in He, and 0.7–8 mbar (0.5–6 Torr) in N 2 . Reduced falloff curves extrapolated with F c = 0.47 for N 2 at 298 K.

(e) Detection of NO 3 . Experiments were conducted over the pressure range 0.7–10.7 mbar (0.5–8 Torr) and the data evaluated using F c = {2.5 exp(-1950/T) + 0.9 exp(-T/430)} (F c (298 K) = 0.45).

Preferred Values

k0cm3molecule-1s-1{3.7-30 N_2[N2] 3.7×10-30±0.10 N_2[N2]   if   T 298 3.6-30 T 300 PlusMinus -4.1 0.5 N_2[N2]3.6×10-30 (T/ 300 )( -4.1 ±0.5) N_2[N2]  if   200 T 300

Comments on Preferred Values

The preferred values are based on the data of Orlando et al. (1991), and the falloff extrapolation from Hahn et al. (2000) using the theoretically derived F c = 0.35 independent of the temperature between 200 and 400 K. The temperature dependence is from the theoretical modelling of Hahn et al. (2000). Different choices of F c lead to different values of the extrapolated k 0 and k , although the various representations all agree well with the experimental data.

Rate Coefficient Data: High-pressure rate coefficients

Absolute Rate Coefficients

Rate Coefficient (k) / Temperature / ReferenceTechniques and Comments
cm3molecule-1s-1Kelvin
2.1×10 -10 exp(-1360/T)262–295Connell and Johnston, 1979(a)
2.2×10 -12 298
1.5×10 -10 exp(-1610/T)285–384Viggiano et al., 1981(b)
6.8×10 -13 298
(2.2 ± 0.5)×10 -12 293Croce de Cobos et al., 1984(c)
(1.65 ± 0.15)×10 -12 (T/300) -(0.4±0.5) 236–358Kircher et al., 1984FP-A (d)
1.85×10 -12 298Smith et al., 1985DF-A (e)
1.7×10 -12 (T/300) -0.2 236–358Orlando et al., 1991DF-LIF (f)
(1.9 ± 0.3)×10 -12 (T/300) 0.2 300–400Hahn et al., 2000PLP (g)

Comments

(a) See comment (a) for k 0 .

(b) See comment (b) for k 0 . Data obtained from extrapolation of data in a relatively narrow pressure range near to the center of the falloff curve.

(c) Laser flash photolysis of N 2 O in the presence of NO 2 . NO 3 radicals were monitored by visible absorption under pseudo-first order conditions. The falloff curve was measured over the pressure range 1–200 bar in N 2 , and extrapolated with F c = 0.34.

(d) See comment (c) for k 0 .

(e) See comment (d) for k 0 .

(f) See comment (e) for k 0 .

(g) See comment (c); measurements over the pressure range 30–900 bar evaluated with k 0 from Orlando et al. (1991) and F c = 0.35.

Preferred Values

kcm3molecule-1s-1{1.9-121.9×10-12±0.2  if   T 298 1.9-12 T 300 PlusMinus 0.2 0.61.9×10-12 (T/ 300 )( 0.2 ±0.6)  if   200 T 400

Comments on Preferred Values

The preferred values are based on the high pressure measurements from Hahn et al. (2000), which within experimental uncertainty agree well with the extrapolated values from Kircher et al. (1984), Smith et al. (1985), Orlando et al. (1991) and Croce de Cobos et al. (1984). The theoretically calculated value of F c = 0.35 does not influence the k -value but influences the extrapolated value of k 0 .

References

  • Connell, P. and Johnston, H. S. , Geophys. Res. Lett. , 6 , 553 , 1979.
  • Croce de Cobos, A. E., Hippler, H. and Troe, J. , J. Phys. Chem. , 88 , 5083 , 1984.
  • Graham, R. A. and Johnston, H. S. , J. Phys. Chem. , 82 , 254 , 1978.
  • Hahn, J., Luther, K. and Troe, J. , Phys. Chem. Chem. Phys. , 2 , 5098 , 2000.
  • Kircher, C. C., Margitan, J. J. and Sander, S. P. , J. Phys. Chem. , 88 , 4370 , 1984.
  • Orlando, J. J., Tyndall, G. S., Cantrell, C. A. and Calvert, J. G. , J. Chem. Soc. Faraday Trans. , 87 , 2345 , 1991.
  • Smith, C. A., Ravishankara, A. R. and Wine, P. H. , J. Phys. Chem. , 89 , 1423 , 1985.
  • Viggiano, A. A., Davidson, J. A., Fehsenfeld, F. C. and Ferguson, E. E. , J. Chem. Phys. , 74 , 6113 , 1981.