Chapter 19, Problem 19.18QAP

Interpretation Introduction

Interpretation:

The ¹H and ³¹P NMR spectra of methyl phosphorous acid P(OCH₃)₃ at 7.05 T should be compared.

Concept introduction:

The theory behind NMR is some nuclei can exist in specific nuclear states in the presence of external magnetic field. NMR detects the transition between these spin states. NMR applies to the nuclei whose spin is not equal to zero. Each nuclei absorbs only a specific frequency. So, NMR detect one type of isotope at a time. So NMR can be used to differentiate between elements which leads to different types of NMR, such as, ¹H NMR, 13C NMR, and ³¹P NMR.

Spin-spin coupling is a phenomenon which is caused by the spin coupling between two chemically different nuclei which are NMR active. This effect is indicated through peak splitting in NMR spectra.