Proton NMR (also
Hydrogen-1 NMR, or
<sup>1</sup>H NMR) is the application of
nuclear magnetic resonance in
NMR spectroscopy with respect to
hydrogen-1 nuclei within the
molecules of a substance, in order to determine the structure of its molecules.R. M. Silverstein, G. C. Bassler and T. C. Morrill,
Spectrometric Identification of Organic Compounds, 5th Ed., Wiley,
1991. In samples where natural
hydrogen (H) is used, practically all of the hydrogen consists of the
isotope <sup>1</sup>H (hydrogen-1; i.e. having a
proton for a nucleus).
Simple NMR spectra are recorded in
solution, and
solvent protons must not be allowed to interfere.
Deuterated (deuterium = <sup>2</sup>H, often symbolized as D) solvents especially for use in NMR are preferred, e.g. deuterated water, D<sub>2</sub>O , deuterated acetone, (CD<sub>3</sub>)<sub>2</sub>CO, deuterated methanol, CD<sub>3</sub>OD,
deuterated dimethyl sulfoxide, (CD<sub>3</sub>)<sub>2</sub>SO, and
deuterated chloroform, CDCl<sub>3</sub>. However, a solvent without hydrogen, such as
carbon tetrachloride, CCl<sub>4</sub> or
carbon disulphide, CS<sub>2</sub>, may also be used.
Historically, deuterated solvents were supplied with a small amount (typically 0.1 %) of
tetramethylsilane (TMS) as an
internal standard for calibrating the
chemical shifts of each analyte proton. TMS is...
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