12030-49-8Relevant articles and documents
Kinetic study of the reaction of Ir(a4F9/2) with CH4, O2, and N2O
Campbell
, p. 9377 - 9381 (1997)
The gas-phase reactivity of ground-state Ir(a4F9/2) with CH4, O2, and N2O is reported. Iridium atoms were produced by the photodissociation of [Ir(CO)2(acac)] and detected by laser-induced fluorescence. The reaction rate of the a4F9/2 state with CH4 is very slow and temperature-dependent. The methane reaction is pressure-independent indicating a bimolecular reaction. The bimolecular rate constant from 398 to 498 K is described in Arrhenius form by (7±5)×10-11 exp(-37±3 kJ/mol/RT) where the uncertainties represent ±2σ. The reaction rates of the a4F9/2 state with O2 and N2O are pressure-dependent, indicating adduct formation. The limiting low-pressure third-order, k0, and limiting high-pressure second-order, k∞, room-temperature rate constants with O2 in nitrogen buffer are (4.8±1.6)×10-30 cm6 s-1 and (3.6±0.4)×10-12 cm3 s-1, respectively. For N2O, k0 and k∞ are (2.2±0.5)×10-33 cm6 s-1 and (5.9±0.8)×10-15 cm3 s-1, respectively. A lower limit for the activation energy for the abstraction of an oxygen atom from N2O to produce IrO is estimated at 45 kJ/mol.
