Chapter 16, Problem 16.47P

Interpretation Introduction

Interpretation:

Using the NMR instrument described in Problem 16.44, suppose that a $\text{C}$ nucleus from a sample generates a signal whose frequency is 11, 250 Hz higher than that from the carbons in TMS. The chemical shift of that carbon atom from the sample is to be determined.

Concept introduction:

The chemical shift is calculated by

$\text{Chemical shift (ppm) = }\frac{{\text{ν}}_{\text{sample}}{\text{-ν}}_{\text{TMS}}}{{\text{ν}}_{\text{op}}}{\text{×10}}^{\text{6}}$

Here, ${\text{ν}}_{\text{sample}}$ is the frequency of the signal of interest, ${\text{ν}}_{\text{TMS}}$ is the frequency of the signal from the protons in TMS, and ${\text{ν}}_{\text{op}}$ is the operating frequency of the NMR spectrometer, all of which are in units of hertz (Hz).