Deuterium quadrupolar splitting

Figure 5 Importance of the right alignment strength. Amide region of the H-1D spectrum of the peptide efrapeptin C in two PDMS/CDCl3 gels with deuterium quadrupolar splittings of the solvent of 9 Hz (A) and 35 Hz (B). The increased alignment strength leads to lines of a 60 Hz of the amide signals which usually prohibits accurate extraction of RDCs.

Table 2 Deuterium quadrupolar splitting (Av ) for the a-CD2 palmitic acid in the different lipid mixtures...

The conformation of the spacer can be estimated by using samples carrying a per-deuterated n-alkane sequence. The following expression may be adopted for the deuterium quadrupolar splittings (Avi) due to the ith methylene unit ... 

Sasanuma, Y, and Abe, A., Conformational anisotropy of n-alkanes dissolved in a nematic solvent a rotational isomeric state analysis of proton-proton dipolar coupling and deuterium quadrupolar splitting data, Polym. J., 23, 117-125 (1991). 

Einstein-Simha coefficient (Ch. 1), Poisson s ratio (Ch. 3), deuterium quadrupolar splitting (Ch. 7), frequency of a structural relaxation process (Ch. 11)... 

Membranes and model membranes exhibit liquid crystalline behavior and this has been exploited in a number of studies to obtain valuable information on the structure and dynamics of membrane associated peptides and proteins as well as on the interaction of the peptides with the membranes themselves. NMR spectroscopy of nuclei such as proton, carbon, deuterium, nitrogen and phosphorus has been utilized for such purposes. Structure elucidation of membrane-associated peptides and proteins in oriented bilayers by solid-state NMR spectroscopy has been reviewed. A survey on the use of static uniaxially oriented samples for structural and topological analysis of membrane-associated polypeptides is available. The theoretical background has been dealt with and a number of examples of applications provided. In addition, ongoing developments combining this method with information from solution NMR spectroscopy and molecular modelling as well as exploratory studies using dynamic nuclear polarization solid-state NMR have been presented. The use of N chemical shift anisotropy, dipolar interactions and the deuterium quadrupolar split-... 

Amphiphiles often have a complex phase behaviour with several liquid crystalline phases These liquid crystalline phases are often characterised by long-range order in one directior together with the formation of a layer structure. The molecules may nevertheless be able tc move laterally within the layer and perpendicular to the surface of the layer. Structura information can be obtained using spectroscopic techniques including X-ray and neutror diffraction and NMR. The quadrupolar splitting in the deuterium NMR spectrum can be... 

Similar observations were made for a sodium clay, with Increasing amounts of the divalent calcium or magnesium Ions (32). In the presence of calcium Ions, one can even witness a change In the sign of the deuterium quadrupolar residual splitting. A similar observation was reported recently with heavy water molecules present In and oriented by an uniaxial mesophase (33). 

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