I’m just going to leave this here, for the next time I (or anyone else) want to determine the in-tube concentration of an NMR sample.[1,2]

Solvent [Residual] in mM Acetic Acid-d4 27.1 Acetone-d6 2.30 Acetonitrile-d3 13.1 Benzene-d6 9.52 Chloroform-d 25.1 Dimethylsulfoxide-d6 2.38 Methanol-d4 12.7 Pyridine-d4 14.8 Tetrahydrofuran-d8 7.78 Toluene-d8 5.94 Water-d2 145

Values are derived from this formula:

1000*(1-X)*d/(MW*Y)

x = the posted deuterium purity (ie. “99.8%” CDCl 3 )

y= number of hydrogen/deterium atoms per molecule.

d = density of the deutero solvent.

MW for residual solvent (ex. CHD 3 O for methanol)

Here’s the spreadsheet.

[1] Low concentration samples can be calculated by using the 13C satellite bands, which are 1/200 the concentration of the standard residual peak.