The 3d Transition Elements

Paradoxical violations of Koopman s theorem with special reference to the 3d transition elements and the lanthanides. R. Ferreira, Struct. Bonding (Berlin), 1976, 31, 1-22 (73). 

Felsche J (1973) The Crystal Chemistry of the Rare-Earth Silicates. 13 99-197 Ferreira R (1976) Paradoxial Violations of Koopmans Theorem, with Special Reference to the 3d Transition Elements and the Lanthanides. 31 1-21 Fichtinger-Schepman AMJ, see Reedijk J (1987) 67 53-89... 

Ferreira, R. Paradoxical Violations of Koopmans Theorem, with Special Reference to the 3d Transition Elements and the Lanthanides. Vol. 31, pp. 1-21. 

The presence of magnetism amongst the 3d transition elements causes magnanese, iron, and cobalt not to obey the structural trend that is observed across the nonmagnetic 4d and 5d series. Manganese takes the a-Mn... 

Similar aspects arise for VO, except that vanadium belongs to the 3d transition element group. The electronic structure of VO is, however, similar to that of NbO and a large isotropic 53V hyperfine interaction arises from a 4s spin density of around 30%. 

TS, and RX methods for x-ray transition probabilities was made and it is demonstrated that relative intensity ratios and shapes of x-ray emission spectra are not so sensitive to the method used. The contributions of the interatomic transitions was estimated for CO and compounds of 3d transition metals. For C K-x-iay emission rates in CO the multi-center effect is found to be important, but in the case of the Kfij Ka ratios for the 3d transition elements the interatomic transitions are almost negligible. 

The exact point at which collapse occurs depends rather critically on the presence and strength of the knee at the edge of the inner well. Being less dramatic, the collapse of d orbitals is also more easily disturbed. Thus, it was found [209] that the radius of the 4s electron in the 3d transition elements is very close to the position of the knee. When the 4s orbital is occupied, the potential experienced by the 3d electrons is... 

Figure 26 also shows another, similar process developed by the Th. Goldschmidt AG in Germany (Domazer 1974). This co-reduction or KOR method introduces a portion of the 3d-transition element (Co, etc.) also as an oxide, the rest as metal powder. This provides more internal heat in the reacting mass. Also, the reaction vessel is evacuated and the calcium vaporized. No hydrogen is involved. The reaction is represented by the following equation ... 

The disadvantage of the pseudo-Hamiltonian is that one does not have very much flexibility in matching the core response to valence electrons with different angular momentum because the restrictions on the mass tensor are too severe, especially for first-row and transition metal atoms (i.e., for the cases with strong nonlocalities). In particular, for transition metals it is not possible to use an Ar core because the first electron must always go into an s state [48]. In fact, this is of secondary importance since for accurate calculations, which are the aim of QMC, one has to include 35 and 3p states in the valence space for the 3d transition elements. 

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