Micromechanical sensing of magnetic force was used to detect nuclear magnetic resonance with exceptional sensitivity and spatial resolution. With a 900 angstrom thick silicon nitride cantilever capable of detecting subfemtonewton forces, a single shot sensitivity of 1.6 x 10(13) protons was achieved for an ammonium nitrate sample mounted on the cantilever. A nearby millimeter-size iron particle produced a 600 tesla per meter magnetic field gradient, resulting in a spatial resolution of 2.6 micrometers in one dimension. These results suggest that magnetic force sensing is a viable approach for enhancing the sensitivity and spatial resolution of nuclear magnetic resonance microimaging.

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Advantages of superconducting quantum interference device-detected magnetic resonance over conventional high-frequency electron paramagnetic resonance for characterization of nanomagnetic materials

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A NMR technique for direct determination of internuclear distances in amorphous solids is described and illustrated with a measurement of the carbon–carbon bond length in acetic acid at −190 °C. The result, 1.488 °A, is sufficiently close to the x-ray value of 1.478 °A to confirm the effectiveness of the overall approach. The pulse sequence used, and the ensuing spectral analysis, ensure a very direct measurement of internuclear distances in amorphour solids.

We report a simple, efficient method for carrying out nuclear magnetic resonance (NMR) experiments at high temperature in any NMR probe without modification. The sample tube is coated with a thin film of metal and the rf coil used for the NMR experiment is used to inductively heat the film, thus heating the sample inside the tube. Using this approach, we have obtained both proton and high-resolution carbon-13 NMR spectra at temperatures as high as 730 K.

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