Radiation chemistry of D2O Time dependence of the yields of the radicals at ambient temperature and rate constants for the reactions OD+OD and D+OD up to 200°C
- 1 January 1998
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Journal of the Chemical Society, Faraday Transactions
- Vol. 94 (16) , 2379-2383
- https://doi.org/10.1039/a803140a
Abstract
The yields of eaq -, eaq -+OD and eaq -+D+OD have been measured in D2O at ambient temperature as a function of scavenger concentration. At scavenging powers ⩽107 s-1G(eaq -) is 10% larger than its value in H2O, but for scavenging powers 3×108 s-1 the yields of eaq -, eaq -+OD and eaq -+D+OD are the same in both solvents, indicating that scavenging in the spurs suppresses the reactions leading to the different primary yields. The absorption spectrum of OD is found to be very similar to that of OH, comprising a weak band rising into the UV between 320 and 220 nm with ε250=50±2 mol-1 at 20°C. The shape of the band is the same at 200°C. Rate constants for the reactions OD+OD and D+OD have been measured up to 200°C, on the assumption that ε250 for OD is independent of temperature. As with the corresponding reactions in H2O, they show non-linear Arrhenius behaviour, being close to the diffusion-controlled value at ambient temperature, but an order of magnitude less than this value at 200°C. The values of the rate constants are very similar in both solvents.Keywords
This publication has 0 references indexed in Scilit: