LONGITUDINAL AND TRANSVERSE DIFFUSION COEFFICIENTS OF MASS-IDENTIFIED N+ AND N2+ IONS IN NITROGEN

Longitudinal and transverse diffusion coefficients for mass-identified N+ and N2+ ions in nitrogen in an applied electric field have been measured at room temperature on the EN range from 12 × 10-17 up to 300 × 10-17 V cm2. For EN below about 30 × 10-17 V cm2 the longitudinal and transverse coefficients were found to be equal and to have the value predicted by the Einstein relation. At higher EN both increased with increasing EN, the longitudinal coefficient always being greater than or equal to the transverse. © 1968 The American Physical Society.