Spectrus: Incorrect reference solvent applied after importing NMR data from vendor format

Description
When importing NMR data from certain vendor formats, Spectrus may automatically assign the wrong solvent (e.g., DMSO‑d₆ vs CDCl₃). This leads to systematic shift offsets or incorrect labeling of the residual solvent peak. Users notice that standard solvent signals appear shifted from their expected positions.

Solution

1. Inspect solvent assignment in Spectrus
   • Open the NMR record and check:
     • The solvent field in the experiment metadata.
     • The position of the labeled solvent peak in the spectrum.
2. Confirm the actual solvent used experimentally
   • Verify from the acquisition notes, instrument log, or sample preparation record which deuterated solvent was actually used.
3. Correct the solvent in the record
   • In Spectrus, change the solvent field to the correct one (e.g., select CDCl₃, DMSO‑d₆, MeOD‑d₄).
   • Apply the change; some versions may automatically adjust solvent peak annotation.
4. Re‑reference if necessary
   • Ensure that:
     • The TMS or internal reference is correctly set to 0 ppm (if present).
     • The residual solvent peak now appears at the correct standard chemical shift (within tolerance).
   • If not, manually adjust the reference using the correct solvent peak position.
5. Re‑check assignments and integrals
   • Review key assignments and integrals to ensure they still match expected values after correction.
6. Prevent future confusion
   • Note in internal SOPs:
     • Always confirm the solvent field after import.
     • Correct it immediately if it does not match the experiment notes, especially when multiple solvents are used in a project.