Multiplet Function Now Handles I > 1/2

NMR

SpecHelpers

So fancy!

Author

Bryan Hanson

Published

December 30, 2025

I’ve been very busy with some other projects lately, but my obsession with NMR got the best of me when I saw this post by the Q Magnetics folks. So I decided to modify the multiplet function to handle nuclei with spin > 1/2. Along the way I re-wrote the internals to be more robust and logical (sometimes my first pass can be, shall we say, clunky). Also modified some of the aesthetics of the J-tree slightly. Here’s a couple of examples with I > 1/2.

 # You need `SpecHelpers` version 0.3.2 or higher; there is (as of this writing)
 # an issue with the Mac Binary database, so if you are on Mac you need
 # to install from source using:
 # install.packages("SpecHelpers", type = "source")
library("SpecHelpers")

res <- multiplet(J = 32, I = 1) # CDCl3 observe 13C -> 2H coupling

res <- multiplet(J = 1.13, I = 3 / 2, pw = 0.1) # NaBF4 observe 19F -> 11B coupling

res <- multiplet(J = c(10, 7), I = 3 / 2) # something random that looks interesting

Reuse

CC BY 4.0

Citation

BibTeX citation:

@online{hanson2025,
  author = {Hanson, Bryan},
  title = {Multiplet {Function} {Now} {Handles} {I} \textgreater{} 1/2},
  date = {2025-12-30},
  url = {http://chemospec.org/posts/2025-12-30 Now-With-I/NowWithI.html},
  langid = {en}
}

For attribution, please cite this work as:

Hanson, Bryan. 2025. “Multiplet Function Now Handles I > 1/2.” December 30, 2025. http://chemospec.org/posts/2025-12-30 Now-With-I/NowWithI.html.