Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects

Thesis/Dissertation · Thu Jan 01 00:00:00 EST 2004

DOI:https://doi.org/10.2172/836811· OSTI ID:836811

Urban, Jeffry Todd ^[1]

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1. Univ. of California, Berkeley, CA (United States)

Experimental and theoretical research conducted in two areas in the field of nuclear magnetic resonance (NMR) spectroscopy is presented: (1) studies of the coherent quantum-mechanical control of the angular momentum dynamics of quadrupolar (spin I > 1/2) nuclei and its application to the determination of molecular structure; and (2) applications of the long-range nuclear dipolar field to novel NMR detection methodologies.The dissertation is organized into six chapters. The first two chapters and associated appendices are intended to be pedagogical and include an introduction to the quantum mechanical theory of pulsed NMR spectroscopy and the time dependent theory of quantum mechanics. The third chapter describes investigations of the solid-state multiple-quantum magic angle spinning (MQMAS) NMR experiment applied to I = 5/2 quadrupolar nuclei. This work reports the use of rotary resonance-matched radiofrequency irradiation for sensitivity enhancement of the I = 5/2 MQMAS experiment. These experiments exhibited certain selective line narrowing effects which were investigated theoretically.The fourth chapter extends the discussion of multiple quantum spectroscopy of quadrupolar nuclei to a mostly theoretical study of the feasibility of enhancing the resolution of nitrogen-14 NMR of large biomolecules in solution via double-quantum spectroscopy. The fifth chapter continues to extend the principles of multiple quantum NMR spectroscopy of quadrupolar nuclei to make analogies between experiments in NMR/nuclear quadrupolar resonance (NQR) and experiments in atomic/molecular optics (AMO). These analogies are made through the Hamiltonian and density operator formalism of angular momentum dynamics in the presence of electric and magnetic fields.The sixth chapter investigates the use of the macroscopic nuclear dipolar field to encode the NMR spectrum of an analyte nucleus indirectly in the magnetization of a sensor nucleus. This technique could potentially serve as an encoding module for the recently developed NMR remote detection experiment. The feasibility of using hyperpolarized xenon-129 gas as a sensor is discussed. This work also reports the use of an optical atomic magnetometer to detect the nuclear magnetization of Xe-129 gas, which has potential applicability as a detection module for NMR remote detection experiments.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 836811
• Report Number(s): LBNL-56768; R&D Project: 508601; TRN: US0500801
• Resource Relation: Other Information: TH: Thesis (Ph.D.); Submitted to the University of California, Berkeley, CA (US); PBD: 21 Dec 2004
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR MOMENTUM
DETECTION
HAMILTONIANS
IRRADIATION
LINE NARROWING
MAGNETIZATION
MAGNETOMETERS
MOLECULAR STRUCTURE
NITROGEN 14
NUCLEAR MAGNETIC RESONANCE
NUCLEI
OPTICS
QUANTUM MECHANICS
RESOLUTION
RESONANCE
SPECTROSCOPY
SPIN
XENON 129
NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY NMR QUADRUPOLAR NUCLEI NUCLEAR QUADRUPOLE RESONANCE NQR QUANTUM MECHANICS ANGULAR MOMENTUM QUANTUM CONTROL MULTIPLE-QUANTUM MAGIC ANGLE SPINNING MQMAS