The inner mechanism of rare earths elucidated by photo-electron spectra

The ligand mediated pseudohypersensitivity of the 3H4 → 3P2, 3H4 → 3P1, 3H4 → 3P0, and 3H4 → 1D2 transitions of praseodymium(III) complexes in solution media

“…bands as marker bands has increased the importance of so-T h e intensity of hypersensitive transitions (1)(2)(3) has been used extensively to distinguish between outer and inner sphere coordination, in identifying the coordinating sites of ligands (4), in determining the immediate coordination environment, and in predicting the coordination number of lanthanides (5)(6)(7)(8)(9)(10). Hypersensitivity has attracted much attention even though theories proposed to explain the phenomenon are far from quantitative.…”

“…Hypersensitivity has attracted much attention even though theories proposed to explain the phenomenon are far from quantitative. T h e majority of the quantitative work on these intensities has been done in the solid state (1 1-16) though a few of the studies have involved solution spectra (5)(6)(7)(8)(9)(10). D u e to phenomenon such a s isomerization, dissociation, association, solvolysis, etc., the solution spectra can become quite complex, which in turn causes the data to bec o m e only approximate and the reproducibility of the experiment to become questionable.…”

Partly filled shells constituting anti-bonding orbitals with higher ionization energy than their bonding counterparts

“…1) varies in a characteristic way as a function of q, showing two zigzag-curves beginning at q----1 and 8 and having their highest points at q = 7 and 14, and having almost the same value for q and (7 + q) which is an almost unique property of the 4[ group, though Catalan, R6hrtich and Shenstone (31) previously had made similar observations of [Ar] 3d¢ -1 4s and JAr] 3d¢ in monatornic 3d group entities. The The two zigzag curves can be explained by the refined spin-pairing energy theory (20,32,33) in the first half of the 4] shell (q < 7) and ½ L $4f for q above 7. The Landd parameter ~4f increases smoothly from 0.08 eV for Ce(III) to 0.36 eV for Yb(III).…”

“…Hf(IV) compared with the isoelectronic Gd(III) and Lu(III) (20,51) This discrepancy is mainly due to correlation energy in the two-electron system…”

“…It is noteworthy that the configuration b 2 a 1 treated in Eqs. (17)(18)(19)(20) contains only one 4j-like electron, and hence, the dramatic decrease of ~0 is obtained without specific interelectronic repulsion in the partly filled shell. However, one has to recognize a minor, but rather curious inaccuracy in the argument leading to Eq.…”