Study of the energy transfer reaction of N2(a 1Πg, ν′) + CO(X 1Σ, ν″ = 0) under molecular beam conditions

The energy transfer reaction of metastable N2(a 1Πg, ν′) prepared by a dc discharge of high-purity nitrogen with CO(X 1Σ, ν″ = 0) was investigated by measuring the vacuum ultraviolet emission spectra of the electronically excited species CO(A 1Π, ν′) and N2(a 1Πg, ν′) during the collision period under molecular beam conditions. The energy mismatch ≈ΔE≈ and qν′ν″ factors for both CO(A 1Π, ν′ ← X 1Σ, ν″) and N2(a 1Πg, ν′ → X 1Σ, ν″) are the determining factors controlling the branching ratio from one N2(a 1Πg, ν′) donor to different vibrational levels of CO(A 1Π, ν′). A formula to calculate the branching ratio is presented by considering the energy mismatch ≈ΔE≈ and the qν′ν″ factors recalculated using a shifted value of the equilibrium internuclear distance re of N2.