Vibrational relaxation of N+2(X 2Σ+g, ν=1) in collisions with He. A theoretical study

Vibrational relaxation of N+2(X 2Σ+g, ν=1) in collisions with He is studied by means of both the quasiclassical trajectory moment method and a semiclasssical analytical approach. To carry out trajectory calculations the potential-energy surface of N+2–He is modeled using ab initio data. Rate constants k10(T) calculated by the moment method reproduce the plateau-like behavior in the Landau–Teller plot of the experimental values at the near thermal energy limit. Simpler analytical models allowing for the long-range interaction are also used to estimate k10(T). The presented theoretical results are in good qualitative agreement with experimental data.