Theoretical Investigations of Chemical Reactivity of Element 113

The heaviest element identified chemically is Z=112. Using the gas-phase thermochromatography technique, its volatility, i.e., the adsorption enthalpy, ∆Hads, on gold plated detectors located along the chromatography column was investigated and compared to that of Hg [1]. Very recently, results of the first chemical studies on element 114 using the same technique were reported [2,3]. Both elements, 112 and 114, were shown to be very volatile which is explained by their closed, 7s6d, and quasiclosed, 7s7p1/2 , shells, respectively. Element 113 (having the 7s7p1/2 ground state) is to be studied next. It is expected to be also volatile and relatively inert, though less than 112 and 114, due to the relativistic stabilization of the 7s and 7p1/2 electrons. Feasibility experiments have already been conducted for its lighter homolog, Tl [4] Earlier, we have predicted ∆Hads of elements 112 and 114 on inert and gold surfaces by performing 4c-DFT calculations for the atoms adsorbed on very large gold clusters [5]. We have also predicted ∆Hads of element 113 on inert surfaces using result of accurate ab initio DiracCoulomb atomic calculations [6]. It was shown that element 113 should be well transported through the Teflon capillaries from the target chamber to the chemistry setup. In this work, we study reactivity of element 113 and Tl on the basis of the calculations for their M2 and MAu dimers: it was shown that binding energies in MAu are directly related to ∆Hads of M on gold [5]. In addition, we study the stability of hydroxides that can be formed in the oxygen atmosphere over the gold surface. For the calculations, we have used our 4c-DFT method [7]. Very large optimized basis sets were used. Results of the calculations for M2, MAu and MOH (M = Tl and element 113) are given in Table 1 [9].