Block metals versus transition elements

The three rows of J-block metals are shown in the schematic periodic table at the beginning of the chapter. The term transition elements (metals) is also widely used, but rf-block metal and transition element are not interchangeable. A transition element is one for which an atom has an incomplete fi -subshell, or which gives rise to a cation with an incomplete fi -subshell, and thus elements in group 12 (which are within the fi -block) are not transition elements. The elements in the /-block (see Chapter 24) are sometimes called inner transition elements. Throughout our discussions, we shall use the terms fi -block and /-block metals, so being consistent with the use of the terms i-block and / -block elements in earlier chapters. Three further points should be noted  

An important point that must not be forgotten is that d-block metal atoms are, of course, many-electron species, and when we discuss, for example, radial distribution functions of the nd atomic orbitals, we refer to hydrogen- 

This last observation is due to the so-called lanthanoid contraction (the steady decrease in size along the 14 lanthanoid metals between La and Hf see Section 24.3). 

Worked example 19.1 Reduction potentials of the first row d-block metals 

In what way does the value of E° for the Fe (aq)/Fe(s) couple depend on the first two ionization energies of Fe(g)  

An important point that must not be forgotten is that c(-block metal atoms are, of course, many-electron species. 

In this section, we consider physical properties of the d-block metals (see cross-references in Section 19.1 for further details). An extended discussion of properties of the heavier metals is given in Section 22.1. Nearly aU the fi -block metals are hard, ductile and malleable, with high electrical and thermal conductivities. With the exceptions of Mn, Zn, Cd and Hg, at room temperature, the metals possess one of the typical metal structures (see Table 6.2). The metallic radii for 12-coordination (Table 6.2 and 

Metals of the tf-block are (with the exception of the group 12 metals) much harder and less volatile than those of the s-block. The trends in enthalpies of atomization 

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Mathematical cluster chemistry/Metal-metal interactions in transition metal clusters with donor ligands/Electron count versus structural arrangement in clusters based on a cubic transition metal core with bridging Main Group elements/Metalloboranes/ Clusters with interstitial atoms from the p-block How do Wade s rules handle them /Diverse naked clusters of the heavy Main Group elements Electronic regularities and analogies... 

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