Actinide paramagnetic resonance

Electronic Structure. Measurements of paramagnetic susceptibility, paramagnetic resonance, light absorption, fluorescence, and crystal structure, in addition to a consideration of chemical and other properties, have provided a great deal of information about the electronic configuration of the aqueous actinide ions in which the electrons arc in the 5/ shell. There are exceptions, such as U2S3, and subnormal compounds, such as TI12S3, where 6d electrons are present. 

Optical and Electron Paramagnetic Resonance Spectroscopy of Actinide Ions in Single Crystals... 

The formation and stabilization of various oxidation states of actinide positive ions in CaF crystals are described. Paramagnetic resonance and optical spectra are reported for divalent Am and trivalent Cm in these crystals. Tetravalent Cm and Pu, formed as a consequence of the intense alpha radiation, are identified by their optical spectra. 

This is normally found for Be +, Mg + and higher charge cations including some of the electronically diamagnetic transition metal ions, lanthanides and actinides. Paramagnetic transition metal cations can be studied using or D resonance. 

A review and a discussion of the electron paramagnetic resonance of the actinides has been published (Boatner and Abraham 1980). Discussions and references cited in this report are relevant to oxide systems. 

Electron paramagnetic resonance (EPR) measurements for actinide ions are usually made at liquid-helium temperatures in order to lengthen the spin-4attice relaxation time (Tj) so the resonance may be observed [7,8]. Consequently information is obtained only about the ground crystal field state and possibly the first excited state. The spectra are interpreted in terms of an effective spin Hamiltonian ... 

This volume of the Handbook illustrates the rich variety of topics covered by rare earth science. Three chapters are devoted to the description of solid state compounds skutteru-dites (Chapter 211), rare earth-antimony systems (Chapter 212), and rare earth-manganese perovskites (Chapter 214). Two other reviews deal with solid state properties one contribution includes information on existing thermodynamic data of lanthanide trihalides (Chapter 213) while the other one describes optical properties of rare earth compounds under pressure (Chapter 217). Finally, two chapters focus on solution chemistry. The state of the art in unraveling solution structure of lanthanide-containing coordination compounds by paramagnetic nuclear magnetic resonance is outlined in Chapter 215. The potential of time-resolved, laser-induced emission spectroscopy for the analysis of lanthanide and actinide solutions is presented and critically discussed in Chapter 216. 

Five reviews have appeared Nuclear magnetic resonance of paramagnetic compounds , Advances in single- and multi-dimensional NMR spectroscopy of paramagnetic metal complexes , NMR and spin relaxation in dimers , Liquid-liquid extraction and NMR , which contains the use of lanthanide and actinide ions to determine distances, and Lanthanide(III) chelates for NMR biomedical applications . ... 

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