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In this research photolysis of NO₂, N₂O and HNO₃ for vast range of altitudes was investigated using the absorption cross-section data provided by NASA. The calculations were made using a special software computer program. Also the lifetimes of NO₂, N₂O and HNO₃ were calculated. The investigation revealed that the lifetime due to photolysis will be nearly steady and short for NO₂, and will be as long (as there is no overlap with solar fluxes below 50 km altitude) for N₂O. As for nitric acid HNO₃ the lifetime started to increase from 1 day at 25 km altitude to 10 days at the surface of the earth.

The adsorption of N₂O at regular and defect sites of MgO (001) surface has been studied systematically using cluster models embedded in a large array of point charges by density functional method. The calculated results show that the MgO (001) surface with oxygen vacancies exhibits high catalytic reactivity toward N₂O adsorptive-decomposition at variance with the regular MgO surface or the surface with magnesium vacancies. Much elongation of O–N bond of N₂O after adsorption at oxygen vacancy site with O end of N₂O down indicates that O–N bond has been broken with concurrent production of N₂, leaving a regular site instead of the original oxygen vacancy site (F center). Besides, the MgO (001) surface with magnesium vacancies hardly exhibits catalytic reactivity. It can be concluded that N₂O dissociation is likely occurred at MgO (001) surface oxygen vacancy sites, which is consistent with the generally accepted viewpoint in the experiment.

The role of a surface oxygen vacancy in the N₂O dissociation over a Cu₂O surface was studied using density functional theory — generalized gradient approximation periodic calculations. To perform this study, surface slab model — surface cell was used. The results indicated that N₂O adsorption properties were associated with the surface oxygen vacancies. The presence of a surface oxygen vacancy, prepared by removing one O_SUF atom from supercell, makes the N₂O decomposition possible, which was believed to occur at a oxygen vacancy site. The N₂O decomposition at the surface oxygen vacant site depends on whether the molecule is adsorbed with the O- or N-end on a vacancy. For the first case, the reaction proceeds spontaneously, which leads to an ejection of N₂ from the surface and the rest of the oxygen atoms occupying the vacancy. In the second case, even though there is an elongation of both N–N and N–O bonds, the dissociation is unfeasible due to very small adsorption energy and high activation energy. The role of the defective surface with surface oxygen vacancy is to provide electrons to the adsorbed molecule.