Orbital expansion indirect relativistic

In contrast, the valence d and f orbitals in heavy atoms are expanded and destabilized by the relativistic effects. This is because the contraction of the s orbitals increases the shielding effect, which gives rise to a smaller effective nuclear charge for the d and f electrons. This is known as the indirect relativistic orbital expansion and destabilization. In addition, if a filled d or f subshell lies just inside a valence orbital, that orbital will experience a larger effective nuclear charge which will lead to orbital contraction and stabilization. This is because the d and f orbitals have been expanded and their shielding effect accordingly lowered. 

The second (indirect) relativistic effect is the expansion of outer d and f orbitals The relativistic contraction of the s and pi/2 shells results in a more efficient screening of the nuclear charge, so that the outer orbitals which never come to the core become more expanded and energetically destabilized. While the direct relativistic effect originates in the immediate vicinity of the nucleus, the indirect relativistic effect is influenced by the outer core orbitals. It should be realized that though contracted s and pi/2 core (innermore) orbitals cause indirect destabilization of the outer orbitals, relativistically expanded d and f orbitals cause the indirect stabilization of the valence s and p-orbitals. That partially explains the very large relativistic stabilization of the 6s and 7s orbitals in Au and element 112, respectively Since d shells (it is also valid for the f shells) become fully populated at the end of the nd series, there will occur a maximum of the indirect stabilization of the valence s and p orbitals [34],... 

The second (indirect) relativistic effect is responsible for the expansion of outer d and f orbitals Here the relativistic contraction of the s and pi/2 shells results in a more efficient screening of the nuclear charge, and the outer high angular momentum orbitals expand and become energetically destabilized. In turn, the relativistically expanded d and f orbitals cause a small additional... 

The relativistic effects are responsible for radial contraction and energetic stabilization of the s /2 and p /2 shells and for the spin-orbit splitting of shells with Z > 0 into sub-shells with j = 1 — 1/2 and j = I + /2. The indirect relativistic effects are consequences of a screening of the d and / electrons by inner electrons occupying the contracted si/2 and pi/2 orbitals and lead to the radial expansion of the and / shells accompanied by their energetic destabilization [1,2]. 

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