SURFACE ANALYSIS METHOD FOR SOLID SAMPLE USING CP/MAS NMR

摘要

PPROBLEM TO BE SOLVED: To analyze a surface of a solid sample, using a CP/MAS NMR (cross polarization/magic angle rotation nuclear magnetic resonance). PSOLUTION: The surface of the solid sample is brought into contact with a contact liquid comprising water or an organic solvent containingSP1/SPH, and is rotated around an axis inclined at a magic angle in a magnetostatic field. A high-frequency pulse magnetic field having a resonance frequency ofSP1/SPH is applied thereto, the pulse magnetic field is ended to leaveSP1/SPH magnetization of only the contact liquid, and a resonance frequency of an objective nuclide of the sample such asSP13/SPC,SP29/SPSi,SP15/SPN,SP31/SPP and the like is measured after a prescribed diffusion time tSBd/SBlapses. The magnetization starts to get mild in both theSP1/SPHs contained in the sample and the contact liquid, from a time point when the pulse magnetic field is stopped, and a relaxation time is longer in theSP1/SPH of the contact liquid. ASP1/SPH spin of the contact liquid thereby diffuses gradually from the surface to the sample contacting therewith, after theSP1/SPH contained in the sample is relaxed. The magnetization transfers from theSP1/SPH to the nuclide such asSP13/SPC in the sample, in a diffusion process therein. The surface of the solid sample is structure-analyzed by measuring the diffusion process of theSP1/SPH spin asSP13/SPC NMR. PCOPYRIGHT: (C)2008,JPO&INPIT