multiplet: Compute & Possibly Draw an NMR Multiplet with Optional...

In SpecHelpers: Spectroscopy Related Utilities

Compute & Possibly Draw an NMR Multiplet with Optional Annotations

Description

Serves as a teaching and self-study tool to understand complex NMR multiplets. Inspired by the Valiulin book (see the reference). One can draw a multiplet, and optionally draw the splitting tree along with annotations of the J values and guides connecting the tree to the peak maxima.

Usage

multiplet(
  J = c(15, 12, 2),
  pw = 0.5,
  plot = TRUE,
  plotJtree = TRUE,
  showJvalues = TRUE,
  showJtreeGuides = TRUE
)

Arguments

J	Numeric. A vector giving the coupling constants.
pw	Numeric. Half the peak width at half-maximum (HWHM). Passed to makeSpec(), and then lorentzCurve() where it is the gamma argument.
plot	Logical. Shall the multiplet be drawn?
plotJtree	Logical. Shall the Jtree be drawn? plot must also be TRUE in this case, and is set automatically if needed.
showJvalues	Logical. Should the J values be added to the plot? Only relevant if plotJtree = TRUE.
showJtreeGuides	Logical. Shall dotted guides be drawn between the last leaves of the Jtree and the peak maxima? Only relevant if plotJtree = TRUE.

Value

A matrix as produced by makeSpec().

Author(s)

Bryan A. Hanson, DePauw University. [e-mail]

References

Roman A. Valiulin NMR Multiplet Interpretation, 2nd Edition, de Gruyter, 2025.

Examples

# Example 3.1 from Valiulin, a ddt.
res <- multiplet(J = c(16.8, 10.1, 6.7, 6.7))
# Example 3.2 from Valiulin, a tt.
res <- multiplet(J = c(6.1, 6.1, 2.15, 2.15))
# Example 3.3 from Valiulin, a dddd.
res <- multiplet(J = c(12.7, 12.2, 10.0, 4.9))
# Some other nice examples
res <- multiplet(J = c(15, 12, 8, 7), pw = 0.25)
res <- multiplet(J = c(15, 8, 5, 2))

SpecHelpers documentation built on April 4, 2025, 4:42 a.m.