Tick the check marks next to the spectra you wish to calibrate relative to the 1H spectrum. Make sure the calibrated 1H is selected in the drop-down box. Click the button next to the reference button and select "Absolute Reference."ĥ. Calibrate the solvent peak or TMS peak in the 1H spectrum.Ĥ. Acquire a 1H and the X nucleus spectrum of your choosing ( 13C, 31P, 29Si, 11B, etc.)Ģ. Open the 1H and X nucleus spectra in MNova.ģ. **1 % TMS in CDCl3, adamantane = 37.77 ppm and 1.71 ppmġ. *Neat TMS scale =1% TMS CDCl3 13C chemical shifts + 0.71 ppm, Adamantane = 38.48 ppm and 1.82 ppm Reference: Nuclear spin properties and conventions for chemical shifts. Now your X nucleus spectrum is calibrated without having to use an external or internal standard.
Sometimes, internal standards will react with your compound, or the correct internal standard compound can be difficult to obtain. Indirect referencing can provide accurate referencing without having to add an internal standard. Either an internal standard or indirect referencing can be used. When acquiring X nucleus spectrum such as 11B, 31P or 29Si, the spectrum must be referenced to something other than the solvent, since the solvent likely does not contain the nucleus.