Vanadium ground state electronic configuration

Predict the ground-state electron configuration of (a) a vanadium atom and (b) a lead atom. 

The 0 + (vanadyl) ion is one of the most stable oxo-metal species known, and probably the most stable diatomic ion. Most of these properties stem from the ground-state electronic configuration of the vanadium atom, [Ar]3d, which shows similarities to the Cu + d system. The ion also lends itself to study by ESR because of the isotopic purity of the V isotope, its high nuclear spin, / = 7/2, and the single unpaired outer electron. 

Exceptions to predicted configurations You can use the aufbau diagram to write correct ground-state electron configurations for all elements up to and including vanadium, atomic number 23. However, if you were to proceed in this manner, your configurations for chromium, [Ar]4s 3d, and copper, [Ar]4s 3d, would prove to be incorrect. The correct configurations for these two elements are ... 

Because the 4s-electrons are lost first when transition metals form ions, you may prefer to write the ground state electronic configuration of a transition metal with the 4s-subshell coming after the 3d-subshell, as shown below for vanadium, iron, and nickel. This is acceptable, but remember, the 4s-subshell fills before the 3d-subshell in the building-up process. 

As vanadium(m) has a d2 electron configuration with a triply degenerate ground state in octahedral symmetry, pseudooctahedral vanadium(III), in analogy to pseudotetrahedral nickel(II), is expected to display short electronic relaxation times. 

Octahedral Vanadium(III). It has been pointed out by Jorgensen (19) that the vanadium(III) ion may not be the most suitable example on which to study the reduction of interelectronic repulsion parameters. In principle, both the vanadium(III) and the cobalt(II) ions to be discussed below are configurationally instable owing to the influence of the Jahn-Teller effect (76) on the orbitally d enerate ground states Ti, and respectively. However, in contrast to Ej states, it may be expected that the distortion should be relatively small in electronic Ti, and T g states. Since any indication of a dissymmetry is lacking in the electronic spectra studied here, the influence of the Jahn-Teller effect will not be considered farther. 

Hartree-Fock self-consistent field calculations indicate that the energy of an electron in the 4s orbital of vanadium lies above that of the 3d orbital in the ground state configuration, [Ar]3dMs. Explain why [Ar]3d 4s and [Ar]3d are less stable configurations than the ground state. 

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