Accurate ab initio potential for the krypton dimer and transport properties of the low-density krypton gas

Abstract

A new highly accurate potential energy curve for the krypton dimer was constructed using coupled-cluster calculations up to the singles, doubles, triples, and perturbative quadruples level, including corrections for core-core and core-valence correlation and for relativistic effects. The ab initio data points were fitted to an analytic potential which was used to compute the most important transport properties of the krypton gas. The viscosity, thermal conductivity, self-diffusion coefficient, and thermal diffusion factor were calculated by the kinetic theory at low density and temperatures from 116 to 5000 K. The comparisons with literature experimental data as well as with values from other pair potentials indicate that our new potential is superior to all previous ones. The transport property values computed in this work are recommended as standard values over the complete temperature range.

LEVEL: A computer program for solving the radial Schrödinger equation for bound and quasibound levels

“…(26) that is a key feature of the original TT form [48,54]. This structure has been used in a number of published potentials [55][56][57], and the extended version of this form available in LEVEL incorporates most variants found in the recent literature:…”

State-of-the-art ab initio potential energy curve for the krypton atom pair and thermophysical properties of dilute krypton gas

“…Additional bond functions located at the center between the two krypton atoms are utilized to improve the convergence behavior towards the CBS limit in most of the calculations. While Waldrop et al 19 chose bond functions that are identical to the hydrogenic basis functions of the same cardinal number X used for the krypton atoms, we employed only two sets of bond functions, which have proven to be reliable for the determination of interaction energies between noble gas atoms. 1,6,7 The large set of mid-bond functions, denoted by (44332), is characterized by exponents of 0.06, 0.18, 0.54, and 1.62 for s and p functions, 0.15, 0.45, and 1.35 for d and f functions, as well as 0.3 and 0.9 for g functions.…”

State-of-the-art ab initio potential energy curve for the xenon atom pair and related spectroscopic and thermophysical properties

“…[5][6][7] For neon, our group developed a pair potential of reference quality, 8 and later we 9 as well as Patkowski and Szalewicz 10 thoroughly investigated the argon atom pair. Recently, highly accurate Kr-Kr potentials have been developed by Waldrop et al 11 and by our group. 12 The derived thermophysical property data for gaseous neon, 13 argon, 4,14,15 and krypton 11,12 are again of reference quality.…”

“…Recently, highly accurate Kr-Kr potentials have been developed by Waldrop et al 11 and by our group. 12 The derived thermophysical property data for gaseous neon, 13 argon, 4,14,15 and krypton 11,12 are again of reference quality. However, their estimated uncertainties are considerably larger than those for helium because the potential energy curve of the four-electron He-He system can be determined much more accurately than the potential energy curves of the heavier rare gas pairs.…”