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《Chemie in Unserer Zeit》2017,51(2):124-132
The present state of the routine 1D 1H‐ and 13C‐NMR spectroscopy is reported. After a short introduction into the basic theory the current spectrometer and software systems are discussed. Using an example from natural product chemistry the procedures during the analysis of the NMR spectra are explained.  相似文献   

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Characterization of the Protons in Polycrystalline Paratungstates using 1H MAS NMR Investigations 1H MAS NMR experiments are used to characterize the non‐acid protons of the anions in polycrystalline paratungstates by means of the measured isotropic chemical shift values. The investigation of various hydrates of ammonium paratungstate allows a direct proof of protons in NH4 ions and in water molecules while protons of the anions are not detectable. However, for both the potassium and the sodium paratungstates 1H MAS NMR investigations detected the protons of water molecules and the non‐acid protons of the paratungstate anions. Additional 1H broad‐line NMR experiments at 173 K support the interpretation of the results obtained by the 1H MAS NMR investigations. For the NMR signal of the non‐acid protons of the paratungstate anion in the 1H MAS NMR spectra of the potassium salt line‐splitting appears. This refers to the existence of two nonidentical positions of the protons in the crystal lattice and is in agreement with the results of the X‐ray structural analysis.  相似文献   

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