Absolute rate coefficients for the reactions of O(1D) with a series of n-alkanes

Pulsed laser generation of O(1D) coupled to detection of HO by laser induced fluorescence was employed to measure rate coefficients, kn, for the reactions (Rn, n = 1, 2, 3, 5 and 6) O(1D) + n-CnH(2n+2) → HO + (other products). Independent of T (220–300 K) the values obtained (units 10−10 cm3 molecule−1 s−1) were: k1 = (1.7 ± 0.3); k2 = (3.4 ± 0.7); k3 = (4.3 ± 0.9); k5 = (5.1 ± 0.9); and k6 = (6.0 ± 0.9). For k1 satisfactory agreement with the literature was obtained. By contrast, k2 and k3 were a factor of ≈2 smaller than reported in earlier absolute determinations. These results were used to extend the reported correlation between O(1D) reaction cross-section and ionisation potential of collider species.