Stability of the NO+⋅N2 ion cluster

Abstract

The equilibrium constant K for the reaction NO⁺+2N₂?NO⁺⋅N₂+N₂ has been determined mass spectrometrically from 178–273 °K at N₂ pressures of 3–12 Torr. Small quantities of O₂ were added to the gas stream to catalyze the charge exchange between N₄⁺ and NO. By analysis of the K data it was found that ΔH°=−5.04±0.09 kcal/mole and ΔS°=−18.5±0.3 cal/mole °K at 298 °K. By extrapolation of the enthalpy data to 0 °K, the NO⁺–N₂ bond energy was found to be 4.98±0.12 kcal/mole.