Accurate values of transport properties of electrons in water vapor at room temperature are calculated, over a wide range of E/$n_0$ values, from a numerical solution of Boltzmann’s equation via the momentum method introduced earlier [Phys. Rev. A 33, 2068 (1986); 34, 2185 (1986)]. The dominant features of the E/$n_0$ dependence are explained using the approximate momentum-transfer theory. For the electron–water-vapor rotational interactions the Born-approximation cross sections of Y. Itikawa [J. Phys. Soc. Jpn. 32, 217 (1972)] have been used to obtain satisfactory agreement with experiment.

• Received 8 December 1987

DOI:https://doi.org/10.1103/PhysRevA.38.1446