Correlation of lifetimes observed in two vibrational levels of the H2 EF1Σg+ state

The lifetimes were measured for rovibronic levels lying slightly lower than the top of the potential barrier in the H2 EF1Σg+ double-minimum state, with a delayed coincidence method following electron impact excitation from the ground state. Dependence of lifetimes on the rotational levels in a pair of vibrational levels is explained in terms of perturbation caused by rotation–vibration interaction between these levels. Lifetimes of some D1Πu and B′1Σu+ levels were also measured to estimate the cascade effects.