Production of the n2 herman infrared system by the energy pooling reaction of N2(Δ3Σ+u) metastable nitrogen molecules

Molecular N₂ emission, observed from an Ar(³Po, 2) and Xe(³P₂) + N₂ flowing afterglow apparatus, indicates that the energy pooling reaction by 2N₂(A ³Σ⁺_u) generates the emission from the Herman infrared system, which is an unassigned nitrogen band system. A lower limit to the formation rate constant for the upper state of the Herman infrared system was found to be 2.5 × 10^-11 cm³ molecule^?1 s^?1. The information presented here may help in the identification of the upper and lower states of the emission system. The 2N₂(A) energy pooling reaction also forms N₂(B³ Π_g, v? 8) but a rate constant cannot be assigned from the present data.     

SCF CI potential energy surfaces for the HCN α HCN isomerisation reaction

We report X ¹A' and 2 ¹A' potential energy surfaces for HCN. Thermal isomerisation on the ground-state surface is discussed. An avoided crossing between X ¹A' and 2 ¹A' suggests alternative isomerisation mechanisms via this excited state. The X¹A'-2¹A' interaction may also allow the formation of CN(X ²Σ⁺) in photodissociation of XCN molecules.