November 23, 2024, 09:56:37 PM
Forum Rules: Read This Before Posting


Topic: Reporting NMR data  (Read 3850 times)

0 Members and 1 Guest are viewing this topic.

Offline oister

  • Very New Member
  • *
  • Posts: 1
  • Mole Snacks: +0/-0
Reporting NMR data
« on: November 06, 2015, 07:46:00 AM »
I'm having some trouble reporting my H NMR data correctly.
I have a benzene ring substituted at position 1, 3 and 4. This leaves me with 3 aromatic peaks; One of them is a singlet (8.2), but with meta coupling, so it looks like a doublet. In my practical report, should I just say it's a singlet (as no ortho coupling) or should I say it's a doublet (due to meta coupling)?
Thanks :)

Edit... Also, another peak is a double doublet (7.95), first due to the ortho coupling, and then meta. Same question here; should I report this as a d or dd?


Offline Corribus

  • Chemist
  • Sr. Member
  • *
  • Posts: 3550
  • Mole Snacks: +545/-23
  • Gender: Male
  • A lover of spectroscopy and chocolate.
Re: Reporting NMR data
« Reply #1 on: November 06, 2015, 09:40:30 AM »
If it's a doublet, report it as a doublet (d, with coupling value in Hz). If it's a doublet of doublets, report it as a doublet of doublets (dd, with coupling values in Hz).
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

Offline Irlanur

  • Chemist
  • Full Member
  • *
  • Posts: 423
  • Mole Snacks: +32/-4
Re: Reporting NMR data
« Reply #2 on: November 07, 2015, 10:33:06 AM »
The multiplicity you report is the multiplicity you see. Otherwise you will quikly run into problems, because in priniple there is a coupling constant between all the nuclei. What you see only depends on the resolution.

Sponsored Links