Electron configuration of transition metals

Electron configurations of transition metal complexes are governed by the principles described in Chapters. The Pauli exclusion principle states that no two electrons can have identical descriptions, and Hund s rule requires that all unpaired electrons have the same spin orientation. These concepts are used in Chapter 8 for atomic configurations and in Chapters 9 and 10 to describe the electron configurations of molecules. They also determine the electron configurations of transition metal complexes. 

The electron configuration for the Co3+ ion is ls22s22p63s23p63d6. If you missed this, review electron configurations of transitional metals. The Co3+ ion would have a total of 24 electrons 10 pairs of electrons and four unpaired electrons in the 3d orbitals. Atoms in which one or more electrons are unpaired are paramagnetic. 

Table 5.4 4sn3c m electron configurations of transition metal atoms. 

Such matters can be represented in a different way in terms of the d-electron configuration of transition metal ions in a molecular orbital scheme (Fig. 7.113). 

Fig. 7.113. d-Electron configuration of transition-metal ions at the surface of perovskites, for the case of magnanites and of nickelates (below). (Reprinted from J. O M. Bockris and T. Ottagawa, J. Phys. Chem., 87 2966,1983.)... 

The electronic configurations of transition metal ions, like those of main group ions, are determined by removal of the electrons from the shell of highest n value first. Next, electrons may be lost from the d subshell next to the valence shell. The capability of removing a variable number of electrons makes it possible for most transition metals to have ions of different charges. 

The number of states for the nd n = 3, 4, 5) electronic configurations of transition metal ions is equal to the number of combinations. Interelectronic repulsions partially remove the degeneracy, leading to the spectroscopic terms with (25 4- 1)(2L-E 1) degeneracy. In a lattice, the degeneracy of the terms is partially removed by... 

How do the following characteristics apply to the electron configurations of transition metals (Chapter 7)... 

Electron Configurations of Transition Metal Ions In contrast to most main-group ions, transition metal ions rarely attain a noble gas configuration, and the reason, once again, is that energy costs are too high. The exceptions in Period 4 are scandium, which forms Sc ", and titanium, which occasionally forms Ti in some compounds. The typical behavior of a transition element is io form more than one cation by losing all of its ns and some of its (n — l)d electrons. (We focus here on the Period 4 series, but these points hold for Periods 5 and 6 also.)... 

SAMPLE PROBLEM 22.1 Writing Electron Configurations of Transition Metal... 

Write electron configurations of transition metal atoms and ions compare periodic trends in atomic properties of transition elements with those of main-group elements explain why transition elements have multiple oxidation states, how their metallic behavior (type of bonding and oxide acidity) changes with oxidation state, and why many of their compounds are colored and paramagnetic ( 22.1) (SP 22.1) (EPS 22.1 -22.17)... 

A further requirement for the existence of orbital angular momentum due to orbital rotation is that there must not be an electron in the second orbital with the same spin as that in the original orbital. With these rules, it is possible to deduce which electron configuration of transition metal ions will have its orbital angular momentum fully or partially quenched. This information is summarized in Table XIII. 

It is important to note that whereas the VSEPR model may be applicable to p-block species, it is not appropriate to apply it to d-electron configurations of transition metal compounds (see Chapters 20-24). 

Luminescence centers of transition-metal ions The general outer electronic configuration of transition-metal ions (cl-block elements) is (n - ns. ... 

Electron Configurations of Transition Metal Ions In contrast to many main-... 

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