H. Hippler et al., SHOCK WAVE-STUDIES OF THE REACTIONS HO-]H2O+HO2 AND HO+HO2-]H2O+O-2 BETWEEN 930 AND 1680 K(H2O2), The Journal of chemical physics, 103(9), 1995, pp. 3510-3516
Monitoring resonance absorption at the Q(1)(4) line near 308.4 nm, HO
concentration-time profiles were recorded during the thermal decomposi
tion of H2O2 in shock waves between 930 and 1680 K. The results were a
nalyzed with respect to the reactions HO+H2O2-->H2O+HO2 (2) and HO+HO2
-->H2O+O-2 (3). Above 800 K, reaction (2) shows a strong increase of t
he rate constant with temperature. Over the range 240 less than or equ
al to T less than or equal to 1700 K the apparent rate constant is rep
resented as k(2) = [1.7 . 10(18). exp(-14 800 K/T)+2.0 . 10(12) exp (-
215 K/T)] cm(3) mol(-1) s(-1). The rate constant k(3) decreases from a
value of 2.0 . 10(13) at 1100 K to a minimum value of 1.1 . 10(13) at
1250 K, and rises again to a value of 4.5 . 10(13) cm(3) mol(-1) s(-1
) at 1600 K. The anomalous temperature dependences of k(2) and k(3) su
ggest mechanisms involving intermediate complex formation. (C) 1995 Am
erican Institute of Physics.