Statistical theory of unimolecular reactions at low pressures

1981 ◽  
Vol 17 (2) ◽  
pp. 117-125 ◽  
Author(s):  
V. V. Egorov ◽  
N. M. Kuznetsov
Keyword(s):  
Statistical Theory ◽  
Unimolecular Reactions ◽  
Low Pressures

scholarly journals Statistical Theory of Unimolecular Reactions and Intramolecular Dynamics

1983 ◽  
Vol 2 (5-6) ◽  
pp. 203-217 ◽  
Author(s):  
R. A. Marcus
Keyword(s):  
Statistical Theory ◽  
Intramolecular Dynamics ◽  
Unimolecular Reactions ◽  
The Past ◽  
Theoretical Developments

In the present lecture we review experimental and theoretical developments in the field of intramolecular dynamics during the past sixty years. In a concluding section we consider possible implications for intramolecular laser selective chemistry.

Competitive unimolecular reactions at low pressures. The pyrolysis of cyclobutyl chloride

1979 ◽  
Vol 11 (1) ◽  
pp. 11-21 ◽  
Author(s):  
Keith D. King ◽  
Brendan J. Gaynor ◽  
Robert G. Gilbert
Keyword(s):  
Unimolecular Reactions ◽  
Low Pressures

Unimolecular Reactions of Methylcyclobutane at Low Pressures

1969 ◽  
Vol 91 (27) ◽  
pp. 7611-7616 ◽  
Author(s):  
Timothy F. Thomas ◽  
Paul J. Conn ◽  
D. F. Swinehart
Keyword(s):  
Unimolecular Reactions ◽  
Low Pressures

Photochemical studies of unimolecular processes VI. The unimolecular reactions of C 6 H 8 isomers and the interpretation of their photolyses

1974 ◽  
Vol 337 (1609) ◽  
pp. 257-274 ◽  
Keyword(s):  
Internal Conversion ◽  
Excited Electronic State ◽  
Photochemical Reactions ◽  
Quantum Yields ◽  
Unimolecular Reactions ◽  
Parent Molecule ◽  
Deactivation Model ◽  
Low Pressures ◽  
Step Quenching ◽  
Good Agreement

The thermal unimolecular isomerization of hexa-1, trans -3, 5-triene to the cis -compound is shown to obey the rate expression k 1 = (4.5 ± 1.5) x 10 12 exp( — 181.3 + 2.0 kJ mol -1 / RT ) s -1 . At low pressures of cyclohexa-1, 3-diene, it undergoes a thermal unimolecular conversion to benzene and hydrogen via cyclohexa-1, 4-diene; the Arrhenius parameters found for this process are k 2 = (4.7 ± 2.2) x 10 13 exp (— 258 ± 4 kJ mol -1 / RT ) s -1 . From these, other kinetic and thermodynamic data, the theory of unimolecular reactions was used to calculate the quantum yields of the main products in the gas phase photolyses of cis - and trans - hexa-1, 3, 5-triene and cyclohexa-1, 3-diene as a function of pressure. Good agreement with experiment was obtained assuming that all the observed photochemical reactions involved vibrationally exoited molecules formed by internal conversion of the initially populated excited electronic state. A limited amount of cis-trans isomerization may occur in the excited electronic states of the hexatrienes. A step-ladder deactivation model with ∆ E = 25 kJ mol -1 for the parent molecule gave good agreement with the experiments, in which there is clear evidence of multi-step quenching. It is deduced from their photochemistry that the trans and cis hexa-1, 3, 5 trienes differ in enthalpy by 11 kJ mol -1 .

Sign in / Sign up

Export Citation Format

Share Document