Lanthanides overview

Physical Properties. An overview of the metallurgy (qv) and soUd-state physics of the rare earths is available (6). The rare earths form aUoys with most metals. They can be present interstitiaUy, in soUd solutions, or as intermetaUic compounds in a second phase. Alloying with other elements can make the rare earths either pyrophoric or corrosion resistant. It is extremely important, when determining physical constants, that the materials are very pure and weU characteri2ed. AU impurity levels in the sample should be known. Some properties of the lanthanides are Usted in Table 3. 

An Overview of Monodimensional Lanthanide Chains Based on Anisotropic Ions... 

In this chapter, we focus on the use of lanthanides as spin-based hardware for QC. The remainder of this introductory section provides some essential concepts and definitions and then it succinctly describes some of the existing proposals for QC. The second section provides a brief overview of results obtained with spin-based systems other than lanthanides. The following two sections review experiments made on qubits and quantum gates, respectively, based on lanthanides, highlighting their specific properties and advantages for QC applications. 

Here we overview the solution structures of lanthanide complexes of relevance to MRI, with a focus on the progress made during the last decade. 

Hartree-Fock methods overview, 1, 645 lanthanide hydrocarbonyls, 4, 4 polyhedral carboranes, 3, 50 silicon-bridged ansa-titanocenes, 4, 624 titanacycles, 4, 568 zinc species, 2, 316... 

This brief overview has shown that there are many possibilities when choosing ligands for the design of luminescent lanthanide complexes. From the examples shown it is apparent that the most luminescent of the lanthanide complexes are formed when macrocyclic ligands are used that fully or almost fully coordinate the metal centre. It should also be apparent that there are many examples and options available when it comes to choosing possible antenna within the criteria set out above (Sect. 2.3.2). 

To provide an overview of the rare-earth compounds which have been studied under pressure so far, table 1 lists the compounds, with respect to the doped ion and with the respective references. Obviously, Eu has been studied under pressure in much more host matrices than any of the other elements. This situation is similar to the observations made by Gorller-Walrand and Binnemans (1996), who reviewed the experimental data on spectroscopic properties of trivalent lanthanide ions doped into crystalline host matrices at ambient pressure. They found that Nd and Eu alone built up around 50% of all studies. 

Y. Baer and W.-D. Schneider, High-energy spectroscopy of lanthanide materials - An overview 1... 

Bunzli, J.-C.G., 1998. Coordination chemistry of the trivalent lanthanide ions an introductory overview. In Saez Puche, R., Caro, P. (Eds.), Rare Earths. Editorial Complutense, Madrid, pp. 223-259. 

In this chapter, different properties of nonlinear behavior in lanthanide complexes have been overviewed, including brief examination of their optical emission and excitation spectra. A perception of the importance of photophysical relationships of molecular complexes to these phenomena has also been conveyed. 

Since their isolation in 1991,1 N-heterocyclic carbenes (NHCs) have become ubiquitous in organometallic chemistry. In more recent years investigations into the coordination of NHCs to other elements have expanded, and there are examples of their coordination to elements across the whole periodic table. This report gives an overview of NHC complexes of non-transition metal elements, ranging from the s-block elements, through the p-block and on to the lanthanides. 

Hogerheide, M.P., Boersma, J., and van Koten, G. (1996) Intramolecular coordination in Group 3 and lanthanide chemistry. An overview. Coordination Chemistry Reviews, 155, 87. 

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