Thermodynamics of the van der Waals Dimers of O₂, N₂ and the Heterodimer (N₂)(O₂) and Their Presence in Earth’s Atmosphere

Composition of the Water Dimer and the Heterodimers of Water with N2 and O2 in Earth’s Atmosphere

“…Unfortunately, there do not appear to be published laboratory or field-based reports of experimental values of K 12 , so it is not possible to independently ascertain the accuracy of the calculations in the present work. However, the validity of the Stogryn-Hirschfelder method , as a reasonable approach to obtaining K 2 for nonpolar homodimers has been shown before. ,, It has also been used to determine K 12 for (N 2 )­(O 2 ) dimerization using combining rules for the LJ parameters σ 12 and (ε/ k B ) 12 . Until direct experimental data, or accurate values of the heterodimer partition functions are available, the K 12 data in Table may be useful in providing reasonable estimates of the (H 2 O)­(N 2 ) and (H 2 O)­(O 2 ) mole fractions and number concentrations under atmospheric conditions at altitudes below 20 km.…”