Interactions of C+(P-2(J)) with rare gas atoms: incipient chemical interactions, potentials and transport coefficients

摘要

Accurate interatomic potentials were calculated for the interaction of a singly charged carbon cation, C+, with a single rare gas atom, RG (RG = Ne-Xe). The RCCSD(T) method and basis sets of quadruple-zeta and quintuple-zeta quality were employed; each interaction energy was counterpoise corrected and extrapolated to the basis set limit. The lowest C+(P-2) electronic term of the carbon cation was considered, and the interatomic potentials calculated for the diatomic terms that arise from these: (2)Pi and (2)Sigma(+). Additionally, the interatomic potentials for the respective spin-orbit levels were calculated, and the effect on the spectroscopic parameters was examined. In doing this, anomalously large spinorbit splittings for RG=Ar-Xe were found, and this was investigated using multi-reference configuration interaction calculations. The latter indicated a small amount of RG - C+ electron transfer and this was used to rationalize the observations. This is taken as evidence of an incipient chemical interaction, which was also examined via contour plots, Birge-Sponerplots and various population analyses across the C+-RG series (RG= He-Xe), with the latter showing unexpected results. Trends in several spectroscopic parameters were examined as a function of the increasing atomic number of the RG atom. Finally, each set of RCCSD(T) potentials was employed, including spinorbit coupling to calculate the transport coefficients for C+ in RG, and the results were compared with the limited available data.