21.10.2014 Views

Physical Chemistry 3: — Chemical Kinetics — - Christian-Albrechts ...

Physical Chemistry 3: — Chemical Kinetics — - Christian-Albrechts ...

Physical Chemistry 3: — Chemical Kinetics — - Christian-Albrechts ...

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

8.3 Generalized Lindemann-Hinshelwood mechanism 189<br />

(2) With the weak collision assumption (h∆ i ≤ ) made by the so-called nonequilibrium<br />

theories, the bottleneck in the state population falls below the equilibrium<br />

distribution already below 0 (see Fig. 8.14). Using the weak collision<br />

assumption, Troe derived the expression<br />

0 = [M] ( 0 )<br />

<br />

− 0 <br />

(8.69)<br />

where is the so-called collision efficiency ( ≤ 1) whichcanbeexpressedin<br />

terms of the average energy transferred per collision h∆ i. becomes even<br />

smaller than the Hinshelwood above. A simple estimate of the weak collision<br />

effect based on Fig. 8.14 may lead to<br />

0 ≈ 0 − ( − 05) (8.70)<br />

I<br />

Figure 8.13: State populations.

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!