Half-integer spin spectroscopy

Goldbourt, A. and Madhu, P.K. (2005) Multiple-quantum magic-angle spinning high-resolution NMR spectroscopy of half-integer spin quadrupolar nuclei. Annu. Rep. NMR Spectrosc., 54, 81-153. 

Abstract Recent advances in nuclear magnetic resonance spectroscopy of quadrupolar (/> 1/2) nuclei with half-integer spins in solids have been reviewed. The advent of multiple-quantum (MQ) magic-angle spinning (MAS) spectroscopy gave new momentum to the study of quadrupolar nuclei in materials of academic and industrial interest such as min-... 

The second intrusion of the electron spin came through a non-energetic, symmetry requirement, the so-called Eermi-Dirac statistics for systems of identical, half-integer spin particles, which results in total antisymmetry of the Schrbdinger wave function in a combined space and spin coordinate domain. This entails the Pauli exclusion principle (1925) in the framework of the independent-particle, Slater-determinantal model. The expression of atomic and molecular wave functions as iinear combinations of Slater determinants has been the basis of most of the subsequent methodologies of quantum chemistry, thermodynamics, and spectroscopy. 

Rocha et al. have reviewed recent advances in NMR spectroscopy of quadrupolar nuclei with half-integer spins. In particular, B, O, Na, A1, Ga, Nb MQ MAS applications have been considered. A range of related techniques, such as satellite transition (ST) MAS, inverse-STMAS NMR, fast amplitude modulation, and techniques based on the dipolar interactions between quadrupolar and spin-1/2 nuclei (CP MQ MAS and MQ HETCOR) and the recently introduced /-coupling based experiments (/-HMQC), have also been reviewed. 

Xu Y, Barbara TM, Rooney WD and Springer CS (1989) Two-dimensional multiple-quantum NMR spectroscopy of isolated half-integer spin systems. 2. C1 examples. Journal of Magnetic Resonance 83 279-298. 

Gan, Z. (2001) Satellite transition magic-angle spinning nuclear magnetic resonance spectroscopy of half-integer... 

Analysis of molecular motion in solids using NMR spectroscopy has been a developing field during the past decades. In this context, 2H NMR is the most used approach but recently a number of other quadrupolar nuclei have been studied. This includes spin-1 as well as half-integer quadrupolar nuclei such as 7Li and 23Na. 

In this review, we shall introduce some basic concepts about sohd-state NMR of half-integer quadrupolar nuclei and discuss the most useful and promising methods presently available to study them. These include older methods, such as Double Rotation (DOR) and Dynamic Angle Spinning (DAS), and novel techniques including MQMAS, Quadrupolar Phase Adjusted Spinning Sidebands QPASS, SateUite Transition (ST) MAS and Inverse-STMAS NMR, and Fast Amplitude Modulation (FAM). We also discuss several techniques based on dipolar interactions between quadrupolar and spin-1/2 nuclei, such as Cross-Polarization (CP) MQMAS, MQ Heteronuclear Correlation Spectroscopy... 

A. Goldboutt, P.K. Madhu, Multiple-quanmm magic-angle spinning high-resolution soHd state NMR spectroscopy of half-integer quadrupolar nuclei, Monatshefte Fur Chemie 133 (2002) 1497-1534. 

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