Series, actinide lanthanide

Between barium (Group 2, element 56) and lutetium (Group 3, element 71), the 4f orbitals fill with electrons, giving rise to the lanthanides, a set of 14 metals named for lanthanum, the first member of the series. The lanthanides are also called the rare earths, although except for promethium they are not particularly rare. Between radium (Group 2, element 88) and lawrenclum (Group 3, element 103), are the 14 actinides, named for the first member of the set, actinium. The lanthanides and actinides are also known as the inner transition metals. 

The Mott-like transition, a central concept for the description of the actinide metal series, causes the sudden increase of the atomic volumes, encountered when between Pu and Am (Fig. 3). All other properties indicate the onset of a 5f localized behaviour at Am (see Part V) the 5 f pressure, which had contained to smaller values the equilibrium interactinide distance, suddenly gives in, with the withdrawal of the 5f s within the atomic core. The occurrence of such a transition within a series characterized by an unsaturated shell, is a unique phenomenon of the actinide series. In lanthanides, it does not occur except perhaps under pressure in cerium metal the approaching of cerium atoms induces suddenly the itineracy of 4f orbitals and a sudden volume collapse - see Chap. C. Neither it occurs in d-transition metal series, where the atomic volumes have an almost parabolic behaviour when plotted vs. Z (see Fig. 3 and Chap. C). The current... 

Symposium in New York, September 1966. Advances in Chemistry Series 71 Lanthanide and Actinide Chemistry. Fields, P. R., Moeller, T. (eds.). Washington, D. C. American Chemical Society 1966... 

First/-transition series (lanthanides) Second/-transition series (actinides) ... 

No. oiAfoiSf electrons Lanthanide series Actinide series ... 

This synthesis is a general method for preparing metalloporphyrins. It works on the whole series of lanthanide and some actinide metals. With this new procedure, virtually all lanthanide metals can form metalloporphyrin complexes.3... 

The rare earths are divided into the lanthanide group, and the elements scandium and yttrium. The lanthanides constitute a special group of elements that have an atomic structure different from the other elements, although they are somewhat akin to the actinide series. The lanthanides make up a group of elements ranging from atomic number 57 (lanthanum) to 71 (lutetium). They are all very similar to lanthanum, which is the reason for the name lanthanide. The other two rare earths, scandium and yttrium, are somewhat apart from the lanthanide series, and will be treated separately. 

Transition metals lanthanide series, actinide series... 

Bhatt, A.I., Kinoshita, H., Koster, A.L. et al. (2006) Actinide, lanthanide and fission product speciation and electrochemistry in high and low temperature ionic melts, in Separations for the Nuclear Fuel Cycle in the 21st Century, ACS Symposium Series, Vol. 933 Chapter 14, American Chemical Society, pp. 219-231. 

As regards the transition elements, the first row in particular show some common characteristics which define a substantial part of their chemistry the elements of the lanthanide and actinide series show an even closer resemblance to each other. 

Evidence other than that of ion-exchange favours the view of the new elements as an inner transition series. The magnetic properties of their ions are very similar to those of the lanthanides whatever range of oxidation states the actinides display, they always have -1-3 as one of them. Moreover, in the lanthanides, the element gado-... 

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