Molecular dynamics calculations of collision-induced absorption in a gas mixture of neon and krypton

W Fakhardji and P Szabo and MSA El-Kader and M Gustafsson, JOURNAL OF CHEMICAL PHYSICS, 152 (2020).

DOI: 10.1063/5.0006186

We continue the development of the in-house molecular dynamics software package SpaCIAL and test it for the computation of the collision-induced absorption coefficients for a neon (Ne) and krypton (Kr) gas mixture. An apodization procedure for the dipole autocorrelation function is implemented and tested. We also carry out a statistical study of the convergence rate with respect to ensemble size. The resulting absorption coefficients show a good accordance with quantum mechanical results. Comparison with laboratory measurements shows agreement within 10%-20% at T = 295 K. At T = 480 K, a larger difference of 40%-80% is observed, which can presumably be explained by experimental uncertainties. For the study, an empirical (Barker, Fisher, and Watts) interaction-potential Mol. Phys. 21, 657 (1971) for Ne-Kr has been developed. Ab initio coupled cluster with singles and doubles (triples) CCSD(T) potentials for Ne-Ne, Kr-Kr, and Ne-Kr have been computed, as well as the CCSD(T) interaction-induced Ne-Kr dipole moment curve.

Return to Publications page