Relativistic effects in HgHe and HgXe CCSD(T) ground state potential curves. Low‐density viscosity simulations of Hg:Xe mixture

Abstract

The comparison of coupled cluster with single and double excitations and with perturbative correction of triple excitations [CCSD(T)] ground state potential curves of mercury with rare gases (RG): HgHe and HgXe, at several levels of theory is presented. The scalar relativistic (REL) effects and spin-orbit coupling effects in the ground state potential curves of these weakly bounded dimers are considered. The CCSD(T) ground state potential curves at the level of the Dirac-Coulomb Hamiltonian (DCH) are compared with CCSD(T) curves at the level of 4-component spin-free modified DCH, the scalar 2nd order Douglas-Kroll-Hess (DKH2) and the nonrelativistic (NR-LL) (Lévy-Leblond) Hamiltonian. In addition, London-Drude formula and SCF interaction energy curves are employed in the analysis of different contributions of REL effects in dissociation energies of HgRG and Hg(2) dimers. Moreover, the large anharmonicity of the HgHe ground state potential curve is highlighted. The computationally less demanding scalar DKH2 Hamiltonian is employed to calculate the HgXe, Hg(2) , and Xe(2) all electron CCSD(T) ground state potential curves in highly augmented quadruple zeta basis sets. These potential curves are used to simulate the shear viscosity of mercury, xenon, and mercury-xenon (Hg:Xe) mixture.

Spectral signatures of semiconductor clusters: (CdSe)16 isomers

“…The states of isomers with geometrical structures X and XI are appreciably higher in total energy than the states of other isomers considered. It is worth noting that the formation of Cd Cd bonds has to be highly unfavorable since the free-standing Cd 2 dimer is a Van der Waals dimer with a Cd Cd binding energy [37] of only ∼200 cm −1 .…”

Importance of Relativistic Effects and Electron Correlation in Structure Factors and Electron Density of Diphenyl Mercury and Triphenyl Bismuth

“…89,90 Properties related to electron density in the valence region (e.g. dipole moments and/or polarizabilities) [91][92][93][94][95] are not affected by PCE and the same is found for the electron density itself. 39,58,80,88 Nevertheless, a common exploration of PCE in electron density, its Laplacian or Fourier transform for compounds of heavy elements is being worthwhile.…”

Ab initio calculation of structure and transport properties of He…X (X = Zn, Cd, Hg) van der Waals complexes

“…The use of the Einstein formula is free of this disadvantage and the coefficient is calculated from the mean‐square displacements of the particles. [8, 25] N is the number of particles for which the coefficient will be evaluated, d is the length of the box in which the simulation is carried out. Finally, t is the time of the simulation.…”

“…Then the diffusion coefficient is evaluated in a way more consistent with the rigorous statistical approach. [8, 25]…”

“…We have not found any theoretical study on the interaction of helium with 12th group atoms giving transport characteristics and the mixture parameters of the fluid system, such as viscosity data or state behavior properties. However, a detailed study on the He…Hg and the Hg…Xe systems is presented in the work of Bučinský et al[8] and the cationic counterpart to the species studied in the present work were studied by Qing et al[9] and Lee et al[10]…”