Understanding NMR (A2 Only)

Understanding NMR (A2 Only)

At the end of the lesson you will be able to explain the basic principles of Nuclear Magnetic Resonance (NMR) spectroscopy.

What do you already know about Nuclear Magnetic Resonance (NMR) spectroscopy?

Basic NMR Principles

NMR spectroscopy characterizes organic compounds by providing detailed information about the positions and environments of hydrogen and carbon atoms.

Overall spin

Only nuclei with an odd nucleon number, such as 1H and 13C, can be analyzed using NMR.

NMR Theory

In the presence of an external magnetic field, nuclei with an odd nucleon number exhibit overall spin and can align with or against the field, creating different energy states.

Nuclei in a magnetic field

Nuclei in the presence of an external magnetic field exhibit overall spin and can align with or against the field, creating different energy states.

Energy difference and Energy gap

The energy gap between these states falls within the radio frequency range, and transitions between states result in signals on the NMR spectrum.

NMR signals and Different chemical environments

Signals on the NMR spectrum vary depending on the chemical environment of the nuclei, displayed as chemical shifts on the x-axis.

Chemical Shifts

Chemical shifts, denoted by δ in ppm, help identify specific environments of atoms within a molecule using reference tables.

Chemical shift notation and Chemical shift tables

Chemical shift notation in NMR spectra is measured in ppm (parts per million) and can be compared to reference tables to identify specific environments of atoms within a molecule.

Recap - Learning Goals

At the end of the lesson you will understand the information provided by NMR spectra and how it relates to the structure of organic compounds.