Energy spectrum average level density

Asymmetry of the spectrum, defined by skewness jq in (32.7), is positive, if the majority of levels are in the lower part of the spectrum, and negative, if the opposite is true. The excess K2 of the spectra of the majority of atoms with one open shell for 1 < N < 41 + 1 is also positive hence, the density of the levels, while approaching the average energy, grows more rapidly in comparison to the case of normal distribution of the levels. The results of the Hartree-Fock calculations of a2, q and K2 for isoelectronic sequences with an open ndN shell indicate that a grows almost linearly with Z, whereas jq and K2 decrease with increase of Z, more rapidly for larger n. 

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