NMR Calibration with TMS and Solvent Signals

NMR calibration uses reference signals to compare sample peaks with a known standard. In an NMR sample, the absolute absorption frequencies of nuclei are hard to measure directly. A standard internal reference compound is added, and the frequency difference between the reference signal and the sample signals is measured.

Precise measurement of the absolute absorption frequencies of nuclei in a sample is difficult. To overcome this, a standard internal reference compound is added, and the difference between their absorption frequencies is measured.

Internal reference compounds, like tetramethylsilane, or TMS, are chemically inert, soluble in NMR solvents, ...