Electric-field–hindered vibrational autoionization in molecular Rydberg states

The vibrational autoionization process of the ${\mathrm{Na}}_2$ nd Rydberg states has been studied in the presence of an electric field. The autoionization lifetime is shown to increase as a function of the electric field. This effect is interpreted in terms of Stark mixing with the high–angular-momentum hydrogenic complex. Moreover, it is shown that the autoionization lifetime grows with the field even in the inter-n-mixing region.