Solid-state Mg NMR spectroscopy

Lipton AS, Heck RW, Primak S et al (2008) Characterization of Mg binding to the DNA repair protein apurinic/apyrimidic endonuclease 1 via solid-state Mg NMR spectroscopy. J Am Chem Soc 130 9332-9341... 

Local environments of main constituent elements (Si, Al, O, Mg, and Ca) in slow-cooled (crystalline) and rapid-quenched (amorphous) blast furnace slags have been investigated using multi-nuclear solid-state NMR spectroscopy. Natural abundance solid-state Mg NMR measurements were made of the disodium salt of magnesium ethylenediaminete-traacetate tetrahydrate. Both MAS and static experiments were employed to determine amongst other parameters, the Cq and the riq of the EFG tensor associated with Mg in this compound. ... 

J. C. C. Freitas, A. Wong and M. E. Smith, Solid-state natural abundance Mg NMR studies of Na2MgEDTA-4H20—a possible new reference compound for Mg NMR spectroscopy. Magn. Reson. Chem., 2008,47,9-15. 

Solid-state NMR spectroscopy was also used to examine the post reaction behavior of pTrMPTrA samples prepared in bulk as thin films, as described in the experimental. All of the spectra in this aging study required a minimum of 720 scans on approximately 50 mg of sample with a 100 s pulse delay to achieve adequate signal/noise. Under these conditions, reliable peak areas could be obtained from the curve fits of the carbonyl region. Figure 3 depicts the evolution of the solid state spectrum of the sample stored under N2 over time and upon heating. The area of the peak at 174 ppm for the carbonyl adjacent to the reacted double bond increases as the peak at 166 ppm for pendant unsaturation decreases. The results of the aging study are given in Table I. 

P. J. Pallister, I. L. Moudrakovski and J. A. Ripmeester, Mg-25 ultra-high field solid state NMR spectroscopy and first principles calculations of magnesium compounds. Phys. Chem. Chem. Phys., 2009,11,11487-11500. 

Tetrahedral and octahedral aluminium sheets in montmorillonite were studied by 27A1 MQ/MAS-NMR spectroscopy.405 19F, 27A1 and 29Si MAS-NMR spectra were used to characterise montmorillonite with various contents of Mg(II) or Zn(II) substituted for aluminium in octahedral sheets.406 Solid-state NMR spectra can be used to characterise and quantify the nanodispersion of variously modified montmorillonite clays in polystyrene matrices.407 27A1 and 29Si MAS-NMR spectra were used to follow hydration processes for Portland cement.408,409... 

Access to ultrahigh fields will also allow the detection of quadrupolar nuclei bound on large structures. See, for example, the recent direct detection by solid-state NMR of potassium cations bound to G-quadruplex struc-tures. The Zn or Mg NMR, for example, will become more accessible in biological systems, an achievement that was still a dream only 20 years ago. The main challenge in the development of new nanohybrid materials is their characterization, many being amorphous. The precise characterization of nanostructures will also strongly rely on the current developments of NMR spectroscopy. 

Recent specifics and the experimental challenges of the solid-state NMR spectroscopies of Mg, Ca, Sr and Ba, which are characterised by low intrinsic sensitivity due to their small magnetic moments and low natural abundance, were discussed in a context of contemporaiy applications to inorganic, organometallic and biological materials as a review. ... 

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