Lutetium ion

The composition may then be described as Ln (OEP) (OEP ). This is easily seen from the paramagnetism of Lu(0EP)2 which has the magnetic moment of a radical, i. e. 1,7 B. M, in the solid state (4) As lutetium ions other than diamagnetic fare not known, only a porphyrin radical state is left to explain the properties, A similar radical state has been found for another doubledecker molecule, lutetium bis(phthalocyaninate), Lu(Pc)2 which is hence to be described as Lu (Pc) (Pc ) (11,12). All the... 

The lutetium ion is present within an approximate tetrahedraUy arranged (T-bonded array of the hgand having an average Lu—C distance of 2.452 A (individual Lu—C distances in Fig. 3). The interbond angles deviate consider-... 

Lu(H20)4(al-P2Wi706i)] is an example of 1 1 complexes of RE with [al-P2Wi706i] ° . In this complex, the lutetium ion is eight-coordinated in a square-antiprism geometry with four oxygen atoms surrounding the vacant site and four water molecules [12],... 

Lu + (4f 4). Since the trivalent lutetium ion has a filled 4f shell, no 4f <— 4f transitions can occur. Lu + is colorless in solutions and single crystals, white in powdered samples. 

Reference has been made already to the existence of a set of inner transition elements, following lanthanum, in which the quantum level being filled is neither the outer quantum level nor the penultimate level, but the next inner. These elements, together with yttrium (a transition metal), were called the rare earths , since they occurred in uncommon mixtures of what were believed to be earths or oxides. With the recognition of their special structure, the elements from lanthanum to lutetium were re-named the lanthanons or lanthanides. They resemble one another very closely, so much so that their separation presented a major problem, since all their compounds are very much alike. They exhibit oxidation state -i-3 and show in this state predominantly ionic characteristics—the ions. 

Separation Processes. The product of ore digestion contains the rare earths in the same ratio as that in which they were originally present in the ore, with few exceptions, because of the similarity in chemical properties. The various processes for separating individual rare earth from naturally occurring rare-earth mixtures essentially utilize small differences in acidity resulting from the decrease in ionic radius from lanthanum to lutetium. The acidity differences influence the solubiUties of salts, the hydrolysis of cations, and the formation of complex species so as to allow separation by fractional crystallization, fractional precipitation, ion exchange, and solvent extraction. In addition, the existence of tetravalent and divalent species for cerium and europium, respectively, is useful because the chemical behavior of these ions is markedly different from that of the trivalent species. 

The same color variety is not typical with inorganic insertion/extraction materials blue is a common transmitted color. However, rare-earth diphthalocyanine complexes have been discussed, and these exhibit a wide variety of colors as a function of potential (73—75). Lutetium diphthalocyanine [12369-74-3] has been studied the most. It is an ion-insertion/extraction material that does not fit into any one of the groups herein but has been classed with the organics in reviews. Films of this complex, and also erbium diphthalocyanine [11060-87-0] have been prepared successfiiUy by vacuum sublimation and even embodied in soHd-state cells (76,77). 

Temperature-jump kinetics. The kinetics of complexation of lutetium(III) with anthrani-late ion was studied by the use of a temperature-jump method.25 The principal reaction is... 

Coordination compounds composed of tetrapyrrole macrocyclic ligands encompassing a large metal ion in a sandwich-like fashion have been known since 1936 when Linstead and co-workers (67) reported the first synthesis of Sn(IV) bis(phthalocyanine). Numerous homoleptic and heteroleptic sandwich-type or double-decker metal complexes with phthalocyanines (68-70) and porphyrins (71-75) have been studied and structurally characterized. The electrochromic properties of the lanthanide pc sandwich complexes (76) have been investigated and the stable radical bis(phthalocyaninato)lutetium has been found to be the first example of an intrinsic molecular semiconductor (77). In contrast to the wealth of literature describing porphyrin and pc sandwich complexes, re-... 

Lutetium is the 60th most abundant element on Earth, and it ranks 15th in the abundance of the rare-earths. It is one of the rarest of the lanthanide series. It is found in monazite sand (India, Australia, Brazil, South Africa, and Florida), which contains small amounts of all the rare-earths. Lutetium is found in the concentration of about 0.0001% in monazite. It is difficult to separate it from other rare-earths by the ion-exchange process. In the pure metallic form, lutetium is difficult to prepare, which makes is very expensive. 

The result of the ion-exchange process in which the +3 ion of lutetium combines with the -1 ion of chlorine to form the binary compound 3LiCl is written as follows ... 

By controlling the stoichiometry of the reaction between lanthanide trichlorides and sodium cyclopentadienide it is possible to replace the chloride ions stepwise. Equihbria are rapidly established, so the addition of Ln(C5H5)3 to one or two equivalents of LnCls will produce M(C5H5)2C1 and M(C5H5)Cl2, respectively. The dichlorides are known only for the lanthanides from samarium to lutetium and are obtained from THF solutions as tris-THF adducts. 

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