Fully relativistic study of intermetallic dimers of group-1 elements K through element 119 and prediction of their adsorption on noble metal surfaces
Spectroscopic properties of group-1 M2 and MAu (M = K, Rb, Cs, Fr, and element 119) were calculated using the 4c-DFT method. The results show that the relativistic contraction and stabilization of the ns(M) AO result in the inversion of trends both in atomic and molecular properties in group 1 beyond Cs. Electronegativity χ of the elements proves to decrease from Cs, the most electropositive element of all elements, to element 119, with its χ value approaching that of Na. Due to the largest relativistic effects on the 8s(119) AO in group 1, bonding in (119)2 appears to be stronger than that of K2, while bonding in 119Au should be the weakest out of all group-1 MAu. Using calculated dissociation energies of M2, sublimation enthalpies, ∆Hsub, of Fr of 77 kJ/mol and element 119 of 94 kJ/mol were estimated using a linear correlation between these quantities in the chemical group. Using the M-Au binding energies, the adsorption enthalpies, -∆Hads, of 106 kJ/mol on gold, 76 kJ/mol on platinum, and 63 kJ/mol on silver were estimated for element 119 via a correlation with known ∆Hads in the chemical group. These moderate ∆Hads values are indicative of a possibility of chromatography adsorption studies of element 119 on the noble metal surfaces.