Temperature dependence of the deexcitation of He(2 3S) by atoms and molecules as studied by pulse radiolysis method

Abstract

The temperature dependence of the rate constants for deexcitation of He(2 ³S) by Ar, Kr, N₂, O₂, CO, NO, CO₂, and C₂H₄ has been measured in the temperature range from 133 to 300 K by a pulse radiolysis method, and thus the collisional energy dependence of the deexcitation cross sections is obtained. The results are interpreted in terms of an electron exchange mechanism. The value of α/β, the ratio of the exponential factor of the potential width Γ(R)=A exp(−αR) to that of the interaction potential V*(R)=B exp(−βR), is obtained for each target molecule. It is found that the value of α/β decreases with the increase of the deexcitation probability.