Interaction potentials for Br−–Rg (Rg=He–Rn): Spectroscopy and transport coefficients

Abstract

High-level ab initio CCSD(T) calculations are performed in order to obtain accurate interaction potentials for the Br(-) anion interacting with each rare gas (Rg) atom. For the Rg atoms from He to Ar, two approaches are taken. The first one implements a relativistic core potential and an aug-cc-pVQZ basis set for bromine, an aug-cc-pV5Z basis set for Rg, and a set of bond functions placed at the midpoint of the Rg-Br distance. The second one uses the all-electron approximation with aug-cc-pV5Z bases further augmented by an extra diffuse function in each shell. Comparison reveals close similarity between both sets of results, so for Rg atoms from Kr to Rn only the second approach is exploited. Calculated potentials are assessed against the previous empirical, semiempirical, and ab initio potentials, and against available beam scattering data, zero electron kinetic energy spectroscopic data, and various sets of the measured ion mobilities and diffusion coefficients. This multiproperty analysis leads to the conclusion that the present potentials are consistently good for the whole series of Br(-)-Rg pairs over the whole range of internuclear distances covered.

Interaction potentials and transport properties of coinage metal cations in rare gases

“…Based on previous results [1][2][3][4][5][6][7][8][9][10][11][12][13][14] and assuming that the present interaction potentials are accurate, we expect that the ion mobilities reported here are accurate to within about 0.2%. This is true both for the mobilities at fixed T 0 as a function of E / n 0 and for the zero-field mobilities as a function of T 0 .…”

“…To date, we have studied 3 He + and 4 He + , 1 Cl − , 2 the alkali metal cations, [3][4][5][6] O − , 7 I − , 8 S − , 9 Hg + and Cd + , 10 O + , 11 F − , 12 Br − , 13 and Tl + . 14 Values calculated from our interaction potentials are in good to excellent agreement with experimental data where they exist, and in each case our potential was found either to be in agreement with the best potential available elsewhere or to be actually the best potential available.…”

Interactions between anionic and neutral bromine and rare gas atoms

“…1 We did not use the CBS extrapolated results since the interaction energies are extremely small at very long R, and, hence, the small errors in the extrapolation may be a large precentage of the actual interaction energies. In order to evaluate the long-range coefficients, we employed the DAV5Z parameters from Tables I and III of our previous work.…”

“…In a recent paper, 1 we reported ab initio interaction potentials for the Br − -Rg anions, with Rg ranging from He to Rn. A multiproperty analysis of results calculated from these potentials led us to conclude that the potentials were consistently good over the whole range of internuclear distances covered.…”

“…A multiproperty analysis of results calculated from these potentials led us to conclude that the potentials were consistently good over the whole range of internuclear distances covered. 1 Second, we analyzed the validity of the atomic approximation to the spin-orbit ͑SO͒ interaction by performing multireference ab initio calculations to obtain the SO coupling matrix elements. Such extensions have proved reliable for similar X-Rg species.…”