Reactions of OH and OD with H sub 2 O sub 2 and D sub 2 O sub 2

Journal Article · Thu Nov 16 00:00:00 EST 1989 · Journal of Physical Chemistry; (USA)

DOI:https://doi.org/10.1021/j100360a021· OSTI ID:7171131

Vaghjiani, G L; Ravishankara, A R ^[1]; Cohen, N ^[2]

---

1. National Oceanic and Atmospheric Administration, Boulder, CO (USA)
2. Aerospace Corp., Los Angeles, CA (USA)

The reactions OH + H{sub 2}O{sub 2} {yields} products (k{sub 1}) and OD + D{sub 2}O{sub 2} {yields} products (k{sub 3}) were studied in the temperature range 273-410 K. The obtained Arrhenius expressions are as follows: k{sub 1} = (2.76 {plus minus} 0.80) {times} 10{sup {minus}12} exp((-110 {plus minus} 60)/T) and k{sub 3} = (1.75 {plus minus} 0.30) {times} 10{sup {minus}12} exp((-320 {plus minus} 20)/T) cm{sup 3} molecule{sup {minus}1} s{sup {minus}1}. The indicated errors are 2{sigma}, including estimated systematic errors. The rate coefficients were independent of the buffer gas (He, N{sub 2}, or SF{sub 6}) used and the pressure (50-500 Torr) employed. The measured kinetic isotope effect, k{sub 1}/k{sub 3}, ranges from 2.7 at 410 K to 3.5 at 273 K. The values of the rate coefficients for OH + D{sub 2}O{sub 2} {yields} products (k{sub 2}) at 273 K and OD + H{sub 2}O{sub 2} {yields} products (k{sub 4}) at 298 K were the same as those of k{sub 3} at 273 K and k{sub 1} at 298 K, respectively. The possible exchange reaction such as OD + H{sub 2}O{sub 2} {yields} OH + HOOD is unimportant, with an upper limit of 2 {times} 10{sup {minus}15} cm{sup 3} molecule{sup {minus}1} s{sup {minus}1} for the rate coefficient at 273 K. Bond energy-bond order (BEBO) calculations using a linear five-particle transition state for a H-abstraction reaction do not yield results that agree with experiments. Transition-state theory calculations using a five-particle nonlinear transition state, (HO)-O-H-O-H, yield results in reasonable agreement with the data.

• OSTI ID: 7171131
• Journal Information: Journal of Physical Chemistry; (USA), Vol. 93:23; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
DEUTERIUM COMPOUNDS
REACTION KINETICS
HYDROGEN PEROXIDE
DATA ANALYSIS
EXPERIMENTAL DATA
HYDROXIDES
ISOTOPE EFFECTS
MEASURING INSTRUMENTS
MEASURING METHODS
MEDIUM TEMPERATURE
DATA
HYDROGEN COMPOUNDS
INFORMATION
KINETICS
NUMERICAL DATA
OXYGEN COMPOUNDS
PEROXIDES
400000* - Chemistry
400202 - Isotope Effects
Isotope Exchange
& Isotope Separation