CMR - Concepts in Magnetic Resonance - up to Jul. 11, 2008

CMR - Concepts in Magnetic Resonance - up to Jul. 11, 2008

Highlights: NMR of chiral compounds; and some must reads, including an overview of NMR relaxation (good for newbies) and an excellent tutorial on CP/MAS by David Rovnyak.

Concepts in Magnetic Resonance Part A
Volume 32A Issue 3, Pages 201 - 218
Published Online: 1 May 2008
NMR studies of chiral organic compounds in non-isotropic phases
by Marek J. Potrzebowski, Agata Jeziorna, S[lstrok]awomir Ka[zacute]mierski

In this article, new applications and perspectives of one- and two-dimensional NMR spectroscopy for study of chiral organic compounds in the non-isotropic phases (solid state and liquid crystals) are presented. The review is organized into five sections. In the first part, theoretical background and short introduction to solid state NMR are shown. The second part presents how NMR isotropic chemical shift can be used for distinguishing of racemates and enantiomers. In the third section, the power of the ODESSA pulse sequence for investigation of racemates, enantiomers and establishing of enantiomeric excess are discussed. The fourth part shows the application of analysis of principal elements of chemical shift tensors obtained by means of 2D NMR techniques for searching of absolute configuration and conformational changes in the solid state. The final part presents recent achievements of chiral liquid crystals NMR methodology for study of chiral compounds. © 2008 Wiley Periodicals, Inc. Concepts Magn Reson Part A 32A:201-218, 2008.

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Concepts in Magnetic Resonance Part A
Volume 32A Issue 3, Pages 168 - 182
Published Online: 1 May 2008

Beyond excitation NMR relaxation
by Armando Ariza-Castolo

The understanding of NMR relaxation processes allows us to comprehend a variety of experiments ranging from the recording of spectra to the determination of images. A brief history of NMR spectroscopy, the state of the art of this technique, as well as its comparison with the coupling constants and chemical shifts measured in the condensed phase are presented in this paper. © 2008 Wiley Periodicals, Inc.Concepts Magn Reson Part A 32A: 168-182, 2008.

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Concepts Magn Reson Part A 32A: 254-276, 2008.

Tutorial on analytic theory for cross-polarization in solid state NMR
by David Rovnyak

This tutorial aims to be a self-contained and explicit analysis of the basic cross polarization (CP) solid-state NMR experiment (SSNMR) in the isolated spin-pair approximation using standard quantum mechanical arguments. The general result of obtaining coherence transfer between two dipolar coupled spin-active nuclei while applying radio frequency fields to both nuclei is described, with emphasis on the origin of the well known Hartmann-Hahn matching conditions. No new theory is presented; rather several common analytical methods in SSNMR are demonstrated in the context of cross-polarization under static and magic-angle spinning (MAS) conditions. A background in NMR and quantum mechanics is assumed, however this work attempts to minimize the need for excursions into the literature. This article was written to aid a reader in advancing into more detailed descriptions of CP and dipolar recoupling in general. © 2008 Wiley Periodicals, Inc.