Toward an accurate description of solid-state properties of superheavy elements

Peter Schwerdtfeger,D Rudolph

doi:10.1051/epjconf/201613107004

Abstract

In the last two decades cold and hot fusion experiments lead to the production of new elements for the Periodic Table up to nuclear charge 118. Recent developments in relativistic quantum theory have made it possible to obtain accurate electronic properties for the trans-actinide elements with the aim to predict their potential chemical and physical behaviour. Here we report on first results of solid-state calculations for Og (element 118) to support future atom-at-a-time gas-phase adsorption experiments on surfaces such as gold or quartz.

Highlights

Mendeleev arranged the known elements (60 in 1869) into a Periodic Table according to their atomic weights and recurring chemical properties
A proper foundation for this ordering scheme came through the electronic shell model of Bohr, and later through Schrödinger’s quantum theory providing proper assignments for the ground state electron configurations of the elements
The Periodic Table contains 118 known and named elements finishing with the 7p electronic shell closure at the recently discovered rare gas element 118 (Oganesson, Og) [1]

Summary

Introduction

Mendeleev arranged the known elements (60 in 1869) into a Periodic Table according to their atomic weights and recurring chemical properties. It is currently a challenge for computational chemistry to obtain accurate lattice parameters and cohesive energies for bulk systems [11], especially for the heavier elements where relativistic and electron correlation effects compete with each other [12,13,14,15]. The total energy of the crystal can be decomposed into the individual many-body interaction terms [16, 17] At long range such a many-body decomposition converges fast and one already obtains correct trends in cohesive energies along the rare gas series of elements from a simple sum over diatomic contributions [19]. We present preliminary results using a simple Lennard-Jones (LJ) potential for the two-body term and an Axilrod-Teller (AT) three-body ansatz [18] for the three-body term to obtain first estimates for cohesive energies of the rare gas fcc crystals Rn and Og

Theory

Results

Conclusions