Arrhenius parameters for the reactions of H atoms with PH3 and AsH3

Abstract

Rate constants for H-atom attack on PH 3 and AsH 3 have been measured in flash photolysis experiments in which H atoms were generated by the Hg-sensitised photolysis of H 2 and monitored by Lyman-α absorption. The values obtained for PH 3 , in the temperature range 293472 K, are given by k 1 /cm3 s−1 = (1.09 ± 0.08) × 10−10 exp[(−1048 ± 27)/T]and for AsH 3 , in the temperature range 294–424 K, by k 2 /cm3 s−1 = (2.57 ± 1.30) × 10−10 exp[(−718 ± 160)/T]An evaluation of the available data on H + PH 3 has been carried out, and the best value for the rate constant over the temperature range 200–500 K is recommended to be k 1 /cm3 s−1 = (0.721 ± 0.041) × 10−10 exp[(−887 ± 19)/T]