Relativistic effects on the electronic structure and volatility of group-8 tetroxides MO_4,where M = Ru,Os,and element 108,Hs

摘要

The influence of relativistic effects on properties and volatility of the group-8 tetroxides MO_4,where M = Ru,Os,and element 108,Hs,was studied on the basis of results of the fully relativistic(four component)and nonrelativistic density functional theory calculations.Relativistic effects were shown to increase bond strengths and decrease bond lengths in these molecules.They are responsible for a decrease in molecular polarizabilities and an increase in ionization potentials.The effects are much stronger in HsO_4 than in the lighter congeners.Relativistic effects were also shown to slightly decrease dispersion interaction energies of RuO_4,OsO_4,and HsO_4 with an inert(quartz or silicon nitride)surface,i.e.,they increase volatility of these compounds as studied in the "one-atom-at-a-time" gas-phase chromatography experiments.They do,however,not influence the trend in group 8:both relativistically and nonrelativistically,volatility should change as RuO_4