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Although ca. 1 mln. times less sensitive than 1 H NMR spectroscopy, 13 C NMR spectroscopy is widely used for characterizing organic and organometallic compounds, primarily because 1H-decoupled 13C-NMR spectra are more simple, have a greater sensitivity to differences in the chemical structure, and, thus, are better suited for identifying ...
In all, this database includes more than 15,000 compounds with the associated 300 MHz 1 H and 75 MHz 13 C spectra. The product includes the software necessary to view and handle the NMR data. This database can be purchased as a library through individual or group contracts. The spectra data appear to be stored as images of processed FID data.
Carbon satellites in physics and spectroscopy, are small peaks that can be seen shouldering the main peaks in the nuclear magnetic resonance (NMR) spectrum.These peaks can occur in the NMR spectrum of any NMR active atom (e.g. 19 F or 31 P NMR) where those atoms adjoin a carbon atom (and where the spectrum is not 13 C-decoupled, which is usually the case).
is an example of a nuclide that produces no NMR signal, whereas 13 C, 31 P, 35 Cl and 37 Cl are nuclides that do exhibit NMR spectra. The last two nuclei have spin S > 1 / 2 and are therefore quadrupolar nuclei. Electron spin resonance (ESR) is a related technique in which transitions between electronic rather than nuclear spin levels ...
The 13 C NMR spectra were recorded at several spectrometers with resonance frequencies ranging from 15 MHz to 100 MHz and a resolution ranging from 0.025 to 0.045 ppm. Spectra were acquired using a pulse flip angle of 22.5 – 45 degrees and a pulse repetition time of 4 – 7 seconds. [4]
The spin interaction that is usually employed for structural analyses via solid state NMR spectroscopy is the magnetic dipolar interaction. [8] Additional knowledge about other interactions within the studied system like the chemical shift or the electric quadrupole interaction can be helpful as well, and in some cases solely the chemical shift has been employed as e.g. for zeolites. [9]
13 C NMR Spectrum of DMSO-d 6. Pure deuterated DMSO shows no peaks in 1 H NMR spectroscopy and as a result is commonly used as an NMR solvent. [2] However commercially available samples are not 100% pure and a residual DMSO-d 5 1 H NMR signal is observed at 2.50ppm (quintet, J HD =1.9Hz). The 13 C chemical shift of DMSO-d 6 is 39.52ppm (septet ...
13 Carbon Magnetic Resonance Spectroscopy. In contrast to phosphorus NMR, carbon NMR is an insensitive technique. This arises from the fact that 13 C NMR has a low abundance (1.1%) and carbon's low gyromagnetic ratio. [19]: 93–96 This low abundance is because 12 C does not have a magnetic moment, making it not NMR active, leading to 13 C's ...