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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 ...
Structure and properties Index of refraction, [1] n D: 1.4795 at 20 °C 1.4787 at 21 °C Abbe number? Dielectric constant, [2] ε r: 48 ε 0 at 20 °C Bond strength? Bond length? Bond angle? Magnetic susceptibility? Surface tension [2] 43 dyn/cm at 20 °C Viscosity: 2.14 mPa·s [2] at 20 °C 1.1 mPa·s [1] at 27 °C
For these reasons, 13 C-NMR spectra are usually recorded with proton NMR decoupling. Couplings between carbons can be ignored due to the low natural abundance of 13 C. Hence in contrast to typical proton NMR spectra, which show multiplets for each proton position, carbon NMR spectra show a single peak for each chemically non-equivalent carbon ...
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).
Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula (CH 3) 2 S O.This colorless liquid is the sulfoxide most widely used commercially. It is an important polar aprotic solvent that dissolves both polar and nonpolar compounds and is miscible in a wide range of organic solvents as well as water.
If a spectrum of an unknown chemical compound is available, a reverse search can be carried out by entering the values of the chemical shift, frequency or mass of the peaks in the NMR, FT-IR or EI-MS spectrum respectively. This type of search affords all the chemical compounds in the database that have the entered spectral characteristics. [6]
This way, the number of equivalent sets of carbon atoms in a chemical structure can be counted by counting singlet peaks, which in 13 C spectra tend to be very narrow (thin). Other information about the carbon atoms can usually be determined from the chemical shift , such as whether the atom is part of a carbonyl group or an aromatic ring, etc.
SDBS includes 14700 1 H NMR spectra and 13000 13 C NMR spectra as well as FT-IR, Raman, ESR, and MS data. The data are stored and displayed as an image of the processed data. Annotation is achieved by a list of the chemical shifts correlated to letters which are also used to label a molecular line drawing.