Theoretical investigation of nitric oxide complexes: Nitric oxide with alkali metal atoms; reaction between nitric oxide and ozone

Different methods of computational chemistry were employed to investigate complexes of nitric oxide. Ab initio level of theory was used in the study of the energetics of the interaction of nitric oxide with the first three alkali metals (Li, Na, K). Both singlet and triplet states were explored with HF and MP2 methods combined with four different basis sets (6-31G, 6-31 G(d), 6-311G(d), 6-311+G(d)). Potential energy surfaces (PES) were plotted and examined for M - NO complexes in their singlet and triplet states. Energy gaps between linear and bent structures were calculated and analyzed. Structural parameters were presented for stationary points on the singlet and triplet surfaces of M + NO.; Two different mechanisms of the reaction between nitric oxide and ozone in a gas phase were investigated with the use of ab initio, DFT, and coupled-cluster methods. The difference in two pathways was determined by whether a nitric oxide molecule attacks a side oxygen atom or abstracts the middle oxygen from an ozone molecule. PESs were obtained with different levels of theory for two reaction mechanisms. The more preferable computational methods were proposed for the nitric oxide and ozone system.