2 H NMR spectra and interpretations are presented on a series of samples, each consisting of a deuterium-labeled organic pollutant (trichloroethylene, acetone, pyridine, benzene, or ethylene glycol) adsorbed on a soil component (montmorillonite clay or humic acid). Spectra were obtained over a wide temperature range and using two values of the quadrupolar echo delay period. Computer simulations of line shapes resulting from various forms of local motion of C-2 H moieties provide useful guidelines for interpreting the experimental results. In a few cases, detailed line shape simulations are given. This approach is attractive for elucidation of the detailed motional behaviors of organic pollutants adsorbed in soil.

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13C cross-polarization (CP) and direct-polarization (DP) spectra of an 83 mg sample of a chemical vapor deposited (CVD) diamond film (combined from 12 separate depositions) have been obtained via dynamic nuclear polarization (DNP) combined with magic-angle spinning (MAS). With DNP, the presence of unpaired electron spins in the sample, measured to be 2 × 1018 spins/g, provides a way to enhance the 13C or the “residual” 1H signal by irradiating the sample with microwaves at or near the electron spin resonance (ESR) Larmor frequency; the interactions between the unpaired electrons and protons or 13C spins lead to a transfer of polarization from the electron spin system to the 1H and/or 13C spin systems. No signal for sp2 hybridized carbons could be observed. The DNP-CP-MAS spectrum, obtained in an experiment in which the DNP-enhanced proton polarization is in turn transferred via CP to the 13C spin system, differs significantly from the DNP-DP-MAS spectrum, in which the 13C spins are directly enhanced.

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