Spectroscopic studies magnetism

S. 11.2.2 Nuclear Magnetic Resonance Spectroscopic Studies S. 11.2.3 Infrared Spectroscopic Studies... 

Nickel(ll) is the only common d ion and its spectroscopic and magnetic properties have accordingly been extensively studied. 

Al-Sa ady, A.K.H., Moss, K., McAuliffe, C.A. and Parish, R.V. (1984) Mossbauer and nuclear magnetic resonance spectroscopic studies on Myocrisin , Solganol , Auranofin , and related gold (I) thiolates. Journal of the Chemical Society, Dalton Transactions, (8), 1609-1616. 

Spectroscopic studies [118] of [Cu(5)Br2] suggest NNS coordination and a dimeric halogen bridged complex. This assignment is consistent with non-electrolytic behavior in DMF, but not with a magnetic moment at room temperature of 1.79 B.M. The shift of the thioamide 4 band from 815 cm" to 800 cm on complexation is taken as evidence for coordination of the... 

Beryllium(II) is the smallest metal ion, r = 27 pm (2), and as a consequence forms predominantly tetrahedral complexes. Solution NMR (nuclear magnetic resonance) (59-61) and x-ray diffraction studies (62) show [Be(H20)4]2+ to be the solvated species in water. In the solid state, x-ray diffraction studies show [Be(H20)4]2+ to be tetrahedral (63), as do neutron diffraction (64), infrared, and Raman scattering spectroscopic studies (65). Beryllium(II) is the only tetrahedral metal ion for which a significant quantity of both solvent-exchange and ligand-substitution data are available, and accordingly it occupies a... 

The elimination of the need to use paramagnetic doping of the catalyst will facilitate future spectroscopic studies both in a catalyst bed and in single catalyst pellets. For spatially resolved spectroscopy, it could also be advantageous to use magnetic nuclei with a wider spread of chemical shifts as compared with H. Extension to other classes of reactors and reactions is feasible and will be addressed. 

The reactions of tri-ATZ-butylplumbyllithium with various phosphorus chlorides have been investigated. For example, reaction of the lithium compound with diphenylchlorophosphane afforded hexa-tert-butyldiplumbane and tetraphenyldiphosphane as the isolated products. Analogous reactions with -butyl-substituted phosphorus chlorides yielded (tri-A, 7-butylplumbyl)di- -butylphosphane or tri- z -butylplumbyl(amino)-, t -butylphosphane. These and other molecules were characterized by multinuclear magnetic resonance spectroscopic studies.24... 

Wilson et al. [2] carried out a compositional and solid state nuclear magnetic resonance (NMR) spectroscopic study of humic and fulvic acid and fractions present in soil organic matter. 

Nuclear magnetic resonance has frequently been employed for general studies and for the structural studies of petroleum constituents (Bouquet and BaiUeul, 1982 Hasan et al., 1989). In fact, proton magnetic resonance (PMR) studies (along with infrared spectroscopic studies) were perhaps the first studies of the modem era that allowed stmctmal inferences to be made about the polynuclear aromatic systems that occm in the high-molecular-weight constituents of petroleum. 

Spectroscopic studies on the Fe-Mo protein by EPR and Mossbauer spectroscopy have shown six iron atoms each in a distinctive magnetic environment coupled to an overall S=3/2 spin system (6,7,8) and electron nuclear double resonance (ENDOR) studies suggest one molybdenum per spin system (8). The 5 Fe signals (five or six doublets) observed in the ENDOR spectra (8) indicate a rather asymmetric structure for the Fe/Mo/S aggregate in which the iron atoms roughly can be grouped into two sets of trios, each set having very similar hyperfme parameters. 

Nuclear magnetic resonance (NMR) spectroscopic studies (1H, 13C, and 31P), are consistent with the dipolar ylide structure and suggest only a minor contribution from the ylene structure.135 Theoretical calculations support this view, also.136... 

Geelhoed, J.S. Hiemstra.T. Van Riemsdijk, WH. (1998) Competitive interaction between phosphate and citrate on goethite. Environ. Sci.Techn. 32 2119-2123 Gehring, A.U. Hofmeister, A.M. (1994) The transformation of lepidocrodte during heating a magnetic and spectroscopic study. 

Rajca and co-workers have studied star-branched and dendritic high-spin polyradicals which are potential organic magnets. Representative data were obtained for the model tetra-anionic compound 55. Three redox waves were observed by cyclic voltammetry and differential pulse voltammetry for a four-electron process between the potentials of -2.00 and -1.20 V (vs. SCE). Electrochemical experiments with these materials have usually been performed at 200 K. The polyradicals, which are less stable for systems with more unpaired electrons, have been characterized by spectroscopic studies, ESR data, and SQUID magnetometiy. 

Lin, S.-T., Ding, M.-R, Ghang, C.-W. et al.. Nuclear magnetic resonance spectroscopic study on ionic liquids of l-alkyl-3-methylimidazolium salts. Tetrahedron, 60, 9441,2004. 

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