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Chemical shifts are usually referenced to the signal of TMS. In many cases, it is inconvenient to actually put TMS the sample so it is common practice to use the known chemical shift of the residual solvent signal as the reference. The reference shift is dependent on the temperature of the sample and the type of TMS referencing method used. The reference shift is also affected by the sample so is more accurate for dilute solutions. The accuracy given here is for dilute solutions.
Select the NMR solvent standard from the list:
Choose the nucleus that you are using for your reference from the list:
Select the temperature of the sample in Celsius, Kelvin or Farenheit. The temperature can be calibrated using an NMR thermometer.
Choose the type of TMS referencing method. Usually chemcial shifts are referenced to the 1H signal of TMS in the same sample. The reference is multiplied by a standard factor for other nuclei. This is the first referencing method on the list. 1H of dilute TMS in CDCl3 at 25°C may be used when comparing chemical shifts between samples in different solvents. The chemical shift may also be referenced to the signal of TMS of the observed nucleus, for example the 13C signal of TMS in a 13C spectrum.
R. E. Hoffman "Standardization of chemical shifts of TMS and solvent signals in NMR solvents" Magn. Reson. Chem., 44, 606-616 (2006).
R. E. Hoffman and E. D. Becker "Temperature dependence of the 1H chemical shift of temtramethylsilane in chloroform, methanol and dimethylsulfoxide" J. Magn. Reson., 176, 87-98 (2005) except in the range 294 to 311 K where it was calibration in our laboratory against methanol-d4. 2.5°C each side of the boundaries are smoothed by linear interpolation.
R. E. Hoffman and E. D. Becker R. E. Hoffman and E. D. Becker "Temperature dependence of the 1H chemical shift of temtramethylsilane in chloroform, methanol and dimethylsulfoxide" J. Magn. Reson., 176, 87-98 (2005). This calibration is a compramise between that published by C. Ammann, P. Meier and A. E. Merbach "A simple multinuclear NMR thermometer" J. Magn. Reson., 46, 319-321 (1982) and M. L. Kaplan, F. A. Bovey and H. N. Cheng "Simplified method of calibrating thermometric nuclear magnetic resonance standards" Anal. Chem., 47, 1703-1705 (1975).