Radiation Decomposition of Water at High Temperatures and Pressures

Abstract

A RECENT publication¹ on the absorption spectrum of ${\text{e}}_{{\text{D}}_{\text{2}}\text{O}}^{\text{-}}$ in the temperature range −4 to 390°C includes data on the absorbance of ${\text{e}}_{{\text{D}}_{\text{2}}\text{O}}^{\text{-}}$ as a function of time. In the kinetic analysis of data in the range 300 to 390°C it was not possible to distinguish between three mechanisms which would lead to the values of the observed absorbances; these values were lower than those obtained by calculations involving the use of standard yields and the extrapolation of rate constants from lower temperatures. The mechanisms were, first, the increase of rate constants by factors from 2.5 to 5; second, the increase of G(D) from 0.4 to 10 and G(OD) from 2.9 to 12.5; and, third, the lowering of G(${\text{e}}_{{\text{D}}_{\text{2}}\text{O}}^{\text{-}}$) from 3.1 to 1.1.