Carbon and deuterium nuclear magnetic resonance in solids

Thesis/Dissertation · Thu Jul 01 00:00:00 EDT 1976

DOI:https://doi.org/10.2172/937066· OSTI ID:937066

Shattuck, Thomas Wayne ^[1]

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

In Chapter I we present the results on a study of cross polarization dynamics, between protons and carbon-13 in adamantane, by the direct observation of the dilute, carbon-13, spins. These dynamics are an important consideration in the efficiency of proton enhancement double-resonance techniques and they also provide good experimental models for statistical theories of cross relaxation. In order to test these theories we present a comparison of the experimental and theoretical proton dipolar fluctuation correlation time τ_c, which is experimentally 110 ± 15 μsec and theoretically 122 μsec for adamantane. These double resonance considerations provide the background for extensions to deuterium and double quantum effects discussed in Chapter II. In Chapter II an approach to high resolution nmr of deuterium in solids is described. The m = 1 → -1 transition is excited by a double quantum process and the decay of coherence Q(τ) is monitored. Fourier transformation yields a deuterium spectrum devoid of quadrupole splittings and broadening. If the deuterium nuclei are dilute and the protons are spin decoupled, the double-quantum spectrum is a high resolution one and yields information on the deuterium chemical shifts Δω. The relationship Q(τ) ~ cos 2Δωτ is checked and the technique is applied to a single crystal of oxalic acid dihydrate enriched to ~ 10% in deuterium. The carboxyl and the water deuterium shifts are indeed resolved and the anisotropy of the carboxyl shielding tensor is estimated to be Δσ = 32 ± 3 ppm. A complete theoretical analysis is presented. The extension of cross relaxation techniques, both direct and indirect, to proton-deuterium double resonance is also described. The m = 1 → -1 double quantum transition and the m = ± 1 → 0 single quantum transitions may all be polarized and we present the derivation of the Hartmann-Hahn cross polarization conditions for each case. In addition the dynamics of the double quantum process, for monodeutero benzene are discussed, giving proton dipolar fluctuation correlation times, and spin heat capacities for the double quantum transition.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: US Energy Research and Development Administration (ERDA)
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 937066
• Report Number(s): LBL-5458; TRN: US200820%%409
• Resource Relation: Related Information: Designation of Academic Dissertation: Masters; Academic Degree: M.S.; Name of Academic Institution: UC Berkeley
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ANISOTROPY
BENZENE
CARBON
CARBON 13
CHEMICAL SHIFT
CYCLOALKANES
DECAY
DEUTERIUM
EFFICIENCY
FLUCTUATIONS
FOURIER TRANSFORMATION
MONOCRYSTALS
NUCLEAR MAGNETIC RESONANCE
NUCLEI
OXALIC ACID
POLARIZATION
PROTONS
QUADRUPOLES
RELAXATION
RESOLUTION
RESONANCE
SHIELDING
SPIN
WATER