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Title: Optically enhanced nuclear cross polarization in acridine-doped fluorene

The objective of this work has been to create large polarizations of the dilute /sup 13/C nuclei in the solid state. The idea was to create /sup 1/H polarizations larger than Boltzmann and to use the proton enhanced nuclear induction spectroscopy cross polarization technique to then transfer this large polarization to the /sup 13/C spin system. Optical Nuclear Polarization (ONP) of acridine-doped fluorene single crystals was studied. In addition, ONP of powdered samples of the acridine-doped fluorene was studied. In general, many compounds do not crystallize easily or do not form large crystals suitable for NMR experiments. Powdered, amorphous and randomly dispersed samples are generally far more readily available than single crystals. One objective of this work has been to (first) create large /sup 1/H polarizations. Although large optical proton polarizations in single crystals have been reported previously, optically generated polarizations in powdered samples have not been reported. For these reasons, ONP studies of powdered samples of the acridine-doped fluorene were also undertaken. Using ONP in combination with the proton enhanced nuclear induction spectroscopy experiment, large /sup 13/C polarizations have been created in fluorene single crystals. These large /sup 13/C polarizations have permitted the determination of the seven incongruent chemicalmore » shielding tensors of the fluorene molecule. Part 2 of this thesis describes the proton enhanced nuclear induction spectroscopy experiment. Part 3 describes the ONP experiment. Part 4 is a description of the experimental set-up. Part 5 describes the data analysis for the determination of the chemical shielding tensors. Part 6 presents the results of the ONP experiments performed in this work and the chemical shielding tensors determined.« less
Authors:
Publication Date:
OSTI Identifier:
5193797
Report Number(s):
LBL-14644
ON: DE82018801
DOE Contract Number:
AC03-76SF00098
Resource Type:
Technical Report
Resource Relation:
Other Information: Portions of document are illegible
Research Org:
Lawrence Berkeley Lab., CA (USA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; FLUORENE; POLARIZATION; ACRIDINES; MONOCRYSTALS; POWDERS; SPIN; SPIN ORIENTATION; TENSORS; ANGULAR MOMENTUM; AROMATICS; AZINES; CONDENSED AROMATICS; CRYSTALS; HETEROCYCLIC COMPOUNDS; HYDROCARBONS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; ORIENTATION; PARTICLE PROPERTIES; PYRIDINES 400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)