The pressure dependence of the thermal decomposition of nitrous oxide
was investigated behind shock waves at temperatures between 1570 K and
5100 K and pressures from 0.3 atm to 450 atm. Nitrous oxide concentra
tion profiles were measured using IR emission from the 4.5 mu m v(1) b
and of N2O. The pressure dependence of the measured rate constant was
described using simple Lindemann fits, resulting in the following low-
and high-pressure limiting rate coefficients: k(lo) = 10(14.6+/-0.6)e
xp(-(237+/-5) kJ mol(-1)/RT) cm(3) mol(-1) s(-1) k(l infinity) = 10(12
.1+/-0.4)exp(-(262+/-3) kJ mol(-1)/RT) s(-1) These values were used to
extrapolate current measurements of the rate coefficient to lower tem
peratures, where the agreement with past work is excellent. Therefore
the limiting rate coefficients given above should be suitable for kine
tic modeling over a temperature range of 800-2000 K and pressures up t
o 450 atm. (C) 1996 John Wiley & Sons, Inc.