Peak Identifier
Enter every shift you could not assign, one per box. Each of the 46 listed impurities is ranked by how many of your peaks it accounts for — because one shift on its own is usually ambiguous, and three together usually are not.
A worked example, in CDCl₃
Three leftover ¹H signals at 4.12, 2.05 and 1.26 ppm.
| Impurity | Explains | 4.12 | 2.05 | 1.26 |
|---|---|---|---|---|
| ethyl acetate | 3/3 | 0.00 | 0.00 | 0.00 |
| 2-propanol | 2/3 | +0.08 | · | +0.04 |
| n-hexane | 1/3 | · | · | 0.00 |
Ethyl acetate accounts for all three and lands exactly on each. 2-propanol reaches two, but sits a little off both. Hexane explains only the 1.26 signal — and would have been an entirely plausible answer had you looked that shift up on its own, which is the case for entering the peaks together.
How the ranking works
Compounds are ordered first by how many of your peaks they explain, then by how closely they land.
To look at a single shift instead, use the signal lookup, or see the whole landscape of a solvent in the spectrum view.